United States of America
|Anthem: "The Star-Spangled Banner"|
|Largest city||New York City|
|National language||English (de facto)|
By Hispanic or Latino origin:
|Government||Federal presidential constitutional republic|
|House of Representatives|
from Great Britain
|July 4, 1776|
|March 1, 1781|
|September 3, 1783|
|June 21, 1788|
• Total area
|3,796,742 sq mi (9,833,520 km2) (3rd[b])|
• Water (%)
• Land area
|3,531,905 sq mi (9,147,590 km2) (3rd)|
• 2022 estimate
• 2020 census
|87/sq mi (33.6/km2) (185th)|
|GDP (PPP)||2022 estimate|
|$25.035 trillion (2nd)|
• Per capita
|GDP (nominal)||2022 estimate|
|$25.035 trillion (1st)|
• Per capita
|Gini (2020)|| 46.9|
|HDI (2021)|| 0.921|
very high · 21st
|Currency||U.S. dollar ($) (USD)|
|Time zone||UTC−4 to −12, +10, +11|
• Summer (DST)
|UTC−4 to −10[d]|
|ISO 3166 code||US|
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territories, nine Minor Outlying Islands,[g] and 326 Indian reservations. The United States is also in free association with three Pacific Island sovereign states: the Federated States of Micronesia, the Marshall Islands, and the Republic of Palau. It is the world's third-largest country by both land and total area.[b] It shares land borders with Canada to its north and with Mexico to its south and has maritime borders with the Bahamas, Cuba, Russia, and other nations.[h] With a population of over 333 million,[i] it is the most populous country in the Americas and the third most populous in the world. The national capital of the United States is Washington, D.C. and its most populous city and principal financial center is New York City.
Paleo-Americans migrated from Siberia to the North American mainland at least 12,000 years ago, and advanced cultures began to appear later on. These societies had almost completely declined when Europeans arrived in North America and began colonizing it. The Great Britain's Thirteen Colonies quarreled with the British Crown over taxation and political representation, leading to the American Revolution (1765–1791). After the Revolution, the United States gained independence, the first nation-state founded on Enlightenment principles of liberal democracy.
In the late 18th century, the U.S. began expanding across North America, gradually obtaining new territories, sometimes through war, frequently displacing Native Americans, and admitting new states. By 1848, the United States spanned the continent from east to west. The controversy surrounding the practice of slavery culminated in the secession of the Confederate States of America, which fought the remaining states of the Union during the American Civil War (1861–1865). With the Union's victory and preservation, slavery was abolished by the Thirteenth Amendment.
By 1890, the United States had grown to become the world's largest economy, and the Spanish–American War and World War I established the country as a world power. After Japan's surprise attack on Pearl Harbor in 1941, the U.S. entered World War II on the Allied side. The aftermath of the war left the United States and the Soviet Union as the world's two superpowers, and led to the Cold War, which commenced in 1945 and ended in 1991 with the Soviet Union's dissolution. During the Cold War, both countries engaged in a struggle for ideological dominance but avoided direct military conflict. They also competed in the Space Race, which culminated in the 1969 American spaceflight in which the U.S. was the first nation to land humans on the Moon. Simultaneously, the civil rights movement (1954–1968) led to legislation abolishing state and local Jim Crow laws and other codified racial discrimination against African Americans. With the Soviet Union's dissolution in 1991 and the end of the Cold War, the United States emerged as the world's sole superpower. In 2001, following the September 11 attacks, the United States became a lead member of the Global War on Terrorism, which included the War in Afghanistan (2001–2021) and the Iraq War (2003–2011).
The United States is a federal republic with three separate branches of government, including a bicameral legislature. It is a liberal democracy and has a market economy. It ranks very high in international measures of quality of life, income and wealth, economic competitiveness, human rights, innovation, and education; it has low levels of perceived corruption. The United States has the highest median income per person of any polity in the world. It has high levels of incarceration and inequality and lacks universal health care. As a melting pot of cultures and ethnicities, the U.S. has been shaped by centuries of immigration.
The United States is a highly developed country, and its economy accounts for approximately a quarter of global GDP and is the world's largest by GDP at market exchange rates. By value, the United States is the world's largest importer and second-largest exporter. Although it accounts for just over 4.2% of the world's total population, the U.S. holds over 30% of the total wealth in the world, the largest share held by any country. The United States is a founding member of the United Nations, World Bank, International Monetary Fund, Organization of American States, NATO, the Quadrilateral Security Dialogue, and is a permanent member of the United Nations Security Council. The country is responsible for more than a third of global military spending and is the foremost military power in the world and a leading political, cultural, and scientific force.
The first known use of the name "America" dates to 1507, when it appeared on a world map produced by the German cartographer Martin Waldseemüller in Saint Dié, Lorraine (now northeastern France). On his map, the name is shown in large letters on what would now be considered South America, honoring Amerigo Vespucci. The Italian explorer was the first to postulate that the West Indies did not represent Asia's eastern limit but were part of a previously unknown landmass. In 1538, the Flemish cartographer Gerardus Mercator used the name "America" to refer to the entire Western Hemisphere.
The first documentary evidence of the phrase "United States of America" dates back to a letter from January 2, 1776, written by Stephen Moylan to Joseph Reed, George Washington's aide-de-camp. Moylan expressed his wish to go "with full and ample powers from the United States of America to Spain" to seek assistance in the revolutionary war effort. The first known publication of the phrase "United States of America" was in an anonymous essay in The Virginia Gazette newspaper in Williamsburg, on April 6, 1776.
The second draft of the Articles of Confederation and Perpetual Union, prepared by John Dickinson and completed no later than June 17, 1776, declared "The name of this Confederation shall be the 'United States of America'." The final version of the Articles, sent to the states for ratification in late 1777, stated that "The Stile of this Confederacy shall be 'The United States of America'." In June 1776, Thomas Jefferson wrote the phrase "UNITED STATES OF AMERICA" in all capitalized letters in the headline of his "original Rough draught" of the Declaration of Independence. This draft of the document did not surface until June 21, 1776, and it is unclear whether it was written before or after Dickinson used the term in his June 17 draft of the Articles of Confederation.
The phrase "United States" was originally plural in American usage. It described a collection of states—e.g., "the United States are..." The singular form became popular after the end of the Civil War and is now standard usage. A citizen of the United States is called an "American". "United States", "American", and "U.S." refer to the country adjectivally ("American values", "U.S. forces"). In English, the word "American" rarely refers to topics or subjects not directly connected with the United States.
It is generally accepted that the first inhabitants of North America migrated from Siberia by way of the Bering land bridge and arrived at least 12,000 years ago; however, some evidence suggests an even earlier date of arrival. The Clovis culture, which appeared around 11,000 BC, is believed to represent the first wave of human settlement of the Americas. This was likely the first of three major waves of migration into North America; later waves brought the ancestors of present-day Athabaskans, Aleuts, and Eskimos.
Over time, indigenous cultures in North America grew increasingly sophisticated, and some, such as the pre-Columbian Mississippian culture in the southeast, developed advanced agriculture, architecture, and complex societies. The city-state of Cahokia is the largest, most complex pre-Columbian archaeological site in the modern-day United States. In the Four Corners region, Ancestral Puebloan culture developed from centuries of agricultural experimentation. The Algonquian are one of the most populous and widespread North American native language groups. Historically, the peoples were prominent along the Atlantic Coast and into the interior along the Saint Lawrence River and around the Great Lakes. This grouping consists of the peoples who speak Algonquian languages. Before Europeans came into contact, most Algonquian settlements lived by hunting and fishing, although quite a few supplemented their diet by cultivating corn, beans and squash (the "Three Sisters"). The Ojibwe cultivated wild rice. The Haudenosaunee of the Iroquois, located in the southern Great Lakes region, was established at some point between the twelfth and fifteenth centuries.
Estimating the native population of North America during European contact is difficult. Douglas H. Ubelaker of the Smithsonian Institution estimated a population of 93,000 in the South Atlantic states and a population of 473,000 in the Gulf states, but most academics regard this figure as too low. Anthropologist Henry F. Dobyns believed the populations were much higher, suggesting around 1.1 million along the shores of the Gulf of Mexico, 2.2 million people living between Florida and Massachusetts, 5.2 million in the Mississippi Valley and tributaries, and around 700,000 people in the Florida peninsula.
Claims of very early colonization of coastal New England by the Norse are disputed and controversial. The first documented arrival of Europeans in the continental United States is that of Spanish conquistadors such as Juan Ponce de León, who made his first expedition to Florida in 1513. The Italian explorer Giovanni da Verrazzano, sent by France to the New World in 1525, encountered native inhabitants of what is now New York Bay. Even earlier, Christopher Columbus had landed in Puerto Rico on his 1493 voyage, and San Juan was settled by the Spanish a decade later. The Spanish set up the first settlements in Florida and New Mexico, such as Saint Augustine, often considered the nation's oldest city, and Santa Fe. The French established their own settlements along the Mississippi River and Gulf of Mexico, notably New Orleans and Mobile.
Successful English settlement of the eastern coast of North America began with the Virginia Colony in 1607 at Jamestown and with the Pilgrims' colony at Plymouth in 1620. The continent's first elected legislative assembly, Virginia's House of Burgesses, was founded in 1619. Harvard College was established in the Massachusetts Bay Colony in 1636 as the first institution of higher education. The Mayflower Compact and the Fundamental Orders of Connecticut established precedents for representative self-government and constitutionalism that would develop throughout the American colonies. Many English settlers were dissenting Christians who came seeking religious freedom. The native population of America declined after European arrival for various reasons, primarily from diseases such as smallpox and measles.
In the early days of colonization, many European settlers experienced food shortages, disease, and conflicts with Native Americans, such as in King Philip's War. Native Americans were also often fighting neighboring tribes and European settlers. In many cases, however, the natives and settlers came to depend on each other. Settlers traded for food and animal pelts; natives for guns, tools and other European goods. Natives taught many settlers to cultivate corn, beans, and other foodstuffs. European missionaries and others felt it was important to "civilize" the Native Americans and urged them to adopt European agricultural practices and lifestyles. However, with the increased European colonization of North America, Native Americans were displaced and often killed during conflicts.
European settlers also began trafficking African slaves into Colonial America via the transatlantic slave trade. Because of a lower prevalence of tropical diseases and relatively better treatment, slaves had a much higher life expectancy in North America than in South America, leading to a rapid increase in their numbers. Colonial society was largely divided over the religious and moral implications of slavery, and several colonies passed acts for or against the practice. However, by the turn of the 18th century, African slaves had supplanted European indentured servants as cash crop labor, especially in the American South.
The Thirteen Colonies[j] that would become the United States of America were administered by the British as overseas dependencies. All nonetheless had local governments with elections open to most free men. With very high birth rates, low death rates, and steady settlement, the colonial population grew rapidly, eclipsing Native American populations. The Christian revivalist movement of the 1730s and 1740s known as the Great Awakening fueled interest both in religion and in religious liberty.
During the Seven Years' War (1756–1763), known in the U.S. as the French and Indian War, British forces captured Canada from the French. With the creation of the Province of Quebec, Canada's francophone population would remain isolated from the English-speaking colonial dependencies of Nova Scotia, Newfoundland and the Thirteen Colonies. Excluding the Native Americans who lived there, the Thirteen Colonies had a population of over 2.1 million in 1770, about a third that of Britain. Despite continuing new arrivals, the rate of natural increase was such that by the 1770s only a small minority of Americans had been born overseas. The colonies' distance from Britain had allowed the development of self-government, but their unprecedented success motivated British monarchs to periodically seek to reassert royal authority.
American Revolution and the early federal republic
The American Revolution separated the Thirteen Colonies from the British Empire, and was the first successful war of independence by a non-European entity against a European power in modern history. By the 18th century the American Enlightenment and the political philosophies of liberalism were pervasive among leaders. Americans began to develop an ideology of "republicanism", asserting that government rested on the consent of the governed. They demanded their "rights as Englishmen" and "no taxation without representation". The British insisted on administering the colonies through a Parliament that did not have a single representative responsible for any American constituency, and the conflict escalated into war.
In 1774, the First Continental Congress passed the Continental Association, which mandated a colonies-wide boycott of British goods. The American Revolutionary War began the following year, catalyzed by events like the Stamp Act and the Boston Tea Party that were rooted in colonial disagreement with British governance. The Second Continental Congress, an assembly representing the United Colonies, unanimously adopted the Declaration of Independence on July 4, 1776 (annually celebrated as Independence Day). In 1781, the Articles of Confederation and Perpetual Union established a decentralized government that operated until 1789. A celebrated early turn in the war for the Americans was George Washington leading the Americans to cross the frozen Delaware River in a surprise attack the night of December 25–26, 1776. Another victory, in 1777, at the Battle of Saratoga resulted in the capture of a British army, and led to France and Spain joining in the war against them. After the surrender of a second British army at the siege of Yorktown in 1781, Britain signed a peace treaty. American sovereignty became internationally recognized, and the new nation took possession of substantial territory east of the Mississippi River, from what is today Canada in the north and Florida in the south.
As it became increasingly apparent that the Confederation was insufficient to govern the new country, nationalists advocated for and led the Philadelphia Convention of 1787 in writing the United States Constitution to replace it, ratified in state conventions in 1788. Going into force in 1789, this constitution reorganized the government into a federation administered by three equal branches (executive, judicial and legislative), on the principle of creating salutary checks and balances. George Washington, who had led the Continental Army to victory and then willingly relinquished power, was the first president elected under the new constitution. The Bill of Rights, forbidding federal restriction of personal freedoms and guaranteeing a range of legal protections, was adopted in 1791. Tensions with Britain remained, however, leading to the War of 1812, which was fought to a draw.
Although the federal government outlawed American participation in the Atlantic slave trade in 1807, after 1820, cultivation of the highly profitable cotton crop exploded in the Deep South, and along with it, the use of slave labor. The Second Great Awakening, especially in the period 1800–1840, converted millions to evangelical Protestantism. In the North, it energized multiple social reform movements, including abolitionism; in the South, Methodists and Baptists proselytized among slave populations.
In the late 18th century, American settlers began to expand further westward, some of them with a sense of manifest destiny. The 1803 Louisiana Purchase almost doubled the nation's area, Spain ceded Florida and other Gulf Coast territory in 1819, the Republic of Texas was annexed in 1845 during a period of expansionism, and the 1846 Oregon Treaty with Britain led to U.S. control of the present-day American Northwest. Additionally, the Trail of Tears in the 1830s exemplified the Indian removal policy that forcibly resettled Indians. This further expanded acreage under mechanical cultivation, increasing surpluses for international markets. This prompted a long series of American Indian Wars west of the Mississippi River from 1810 to at least 1890. and eventually, conflict with Mexico. Most of these conflicts ended with the cession of Native American territory and their confinement to Indian reservations. Victory in the Mexican–American War resulted in the 1848 Mexican Cession of California and much of the present-day American Southwest, and the U.S. spanned the continent. The California Gold Rush of 1848–1849 spurred migration to the Pacific coast, which led to the California Genocide and the creation of additional western states. Economic development was spurred by giving vast quantities of land, nearly 10% of the total area of the United States, to white European settlers as part of the Homestead Acts, as well as making land grants to private railroad companies and colleges. Prior to the Civil War, the prohibition or expansion of slavery into these territories exacerbated tensions over the debate around abolitionism.
The Civil War and Reconstruction
Irreconcilable sectional conflict regarding the enslavement of Africans and African Americans ultimately led to the American Civil War. With the 1860 election of Republican Abraham Lincoln, conventions in eleven slave states declared secession and formed the Confederate States of America, while the federal government (the "Union") maintained that secession was unconstitutional and illegal. On April 12, 1861, the Confederacy initiated military conflict by bombarding Fort Sumter, a federal garrison in Charleston harbor, South Carolina. This would be the spark of the Civil War, which lasted for four years (1861–1865) and became the deadliest military conflict in American history. The war would result in the deaths of approximately 620,000 soldiers from both sides and upwards of 50,000 civilians, almost all of them in the South.
Reconstruction began in earnest following the war. While President Lincoln attempted to foster friendship and forgiveness between the Union and the former Confederacy, his assassination on April 14, 1865 drove a wedge between North and South again. Republicans in the federal government made it their goal to oversee the rebuilding of the South and to ensure the rights of African Americans. They persisted until the Compromise of 1877, when the Republicans agreed to cease protecting the rights of African Americans in the South in order for Democrats to concede the presidential election of 1876. Southern white Democrats, calling themselves "Redeemers", took control of the South after the end of Reconstruction, beginning the nadir of American race relations. From 1890 to 1910, the Redeemers established so-called Jim Crow laws, disenfranchising most blacks and some impoverished whites throughout the region. Blacks would face racial segregation nationwide, especially in the South. They also lived under constant threat of vigilante violence, including lynching.
Industrial Age and the Progressive Era
National infrastructure, including telegraph and transcontinental railroads, spurred economic growth and greater settlement and development of the American Old West. After the American Civil War, new transcontinental railways made relocation easier for settlers, expanded internal trade, and increased conflicts with Native Americans. The later inventions of electric light and the telephone would also affect communication and urban life.
Mainland expansion also included the purchase of Alaska from Russia in 1867. In 1893, pro-American elements in Hawaii overthrew the Hawaiian monarchy and formed the Republic of Hawaii, which the U.S. annexed in 1898. Puerto Rico, Guam, and the Philippines were ceded by Spain in the same year, following the Spanish–American War. American Samoa was acquired by the United States in 1900 after the end of the Second Samoan Civil War. The U.S. Virgin Islands were purchased from Denmark in 1917.
Rapid economic development during the late 19th and early 20th centuries fostered the rise of many prominent industrialists. Tycoons like Cornelius Vanderbilt, John D. Rockefeller, and Andrew Carnegie led the nation's progress in the railroad, petroleum, and steel industries. Banking became a major part of the economy, with J. P. Morgan playing a notable role. The American economy boomed, becoming the world's largest.
These dramatic changes were accompanied by growing inequality and social unrest, which prompted the rise of organized labor along with populist, socialist, and anarchist movements. This period eventually ended with the advent of the Progressive Era, which saw significant reforms including health and safety regulation of consumer goods, the rise of labor unions, and greater antitrust measures to ensure competition among businesses and attention to worker conditions.
The rise to world power, The New Deal, and World War II
The United States remained neutral from the outbreak of World War I in 1914 until 1917 when it joined the war as an "associated power" alongside the Allies of World War I, helping to turn the tide against the Central Powers. In 1919, President Woodrow Wilson took a leading diplomatic role at the Paris Peace Conference and advocated strongly for the U.S. to join the League of Nations. However, the Senate refused to approve this and did not ratify the Treaty of Versailles that established the League of Nations.
Around this time, millions of rural African Americans began a mass migration from the South to northern urban centers; it would continue until about 1970. The last vestiges of the Progressive Era resulted in women's suffrage and alcohol prohibition. In 1920, the women's rights movement won passage of a constitutional amendment granting women's suffrage. The 1920s and 1930s saw the rise of radio for mass communication and the invention of early television. The prosperity of the Roaring Twenties ended with the Wall Street Crash of 1929 and the onset of the Great Depression. After his election as president in 1932, Franklin D. Roosevelt responded with the New Deal. The Dust Bowl of the mid-1930s impoverished many farming communities and spurred a new wave of western migration.
At first neutral during World War II, the United States in March 1941 began supplying materiel to the Allies. On December 7, 1941, the Empire of Japan launched a surprise attack on Pearl Harbor, prompting the United States to join the Allies against the Axis powers, and in the following year, to intern about 120,000 Japanese and Japanese Americans. The U.S. pursued a "Europe first" defense policy, leaving the Philippines, an American colony, isolated and alone to fight Japan's invasion and occupation until the U.S.-led Philippines campaign (1944–1945). During the war, the United States was one of the "Four Powers" who met to plan the postwar world, along with Britain, the Soviet Union, and China. The United States emerged relatively unscathed from the war, and with even greater economic and military influence.
The United States played a leading role in the Bretton Woods and Yalta conferences, which signed agreements on new international financial institutions and Europe's postwar reorganization. As an Allied victory was won in Europe, a 1945 international conference held in San Francisco produced the United Nations Charter, which became active after the war. The United States and Japan then fought each other in the largest naval battle in history, the Battle of Leyte Gulf. The United States developed the first nuclear weapons and used them on Japan in the cities of Hiroshima and Nagasaki in August 1945; the Japanese surrendered on September 2, ending World War II.
Cold War and late 20th century
After World War II, the United States financed and implemented the Marshall Plan to help rebuild western Europe; disbursements paid between 1948 and 1952 would total $13 billion ($115 billion in 2021). Also at this time, geopolitical tensions between the United States and Russia led to the Cold War, driven by an ideological divide between capitalism and communism. They dominated the military affairs of Europe, with the U.S. and its NATO allies on one side and the Soviet Union and its Warsaw Pact allies on the other. The U.S. often opposed Third World movements that it viewed as Soviet-sponsored, sometimes pursuing direct action for regime change against left-wing governments. American troops fought the communist forces in the Korean War of 1950–1953, and the U.S. became increasingly involved in the Vietnam War (1955–1975), introducing combat forces in 1965. Their competition to achieve superior spaceflight capability led to the Space Race, which culminated in the U.S. becoming the first nation to land people on the Moon in 1969. While both countries engaged in proxy wars and developed powerful nuclear weapons, they avoided direct military conflict.
At home, the United States experienced sustained economic expansion, urbanization, and a rapid growth of its population and middle class following World War II. Construction of an Interstate Highway System transformed the nation's transportation infrastructure in decades to come. In 1959, the United States admitted Alaska and Hawaii to become the 49th and 50th states, formally expanding beyond the contiguous United States.
The growing civil rights movement used nonviolence to confront racism, with Martin Luther King Jr. becoming a prominent leader and figurehead. President Lyndon B. Johnson initiated legislation that led to a series of policies addressing poverty and racial inequalities, in what he termed the "Great Society". The launch of a "War on Poverty" expanded entitlements and welfare spending, leading to the creation of the Food Stamp Program, Aid to Families with Dependent Children, along with national health insurance programs Medicare and Medicaid. A combination of court decisions and legislation, culminating in the Civil Rights Act of 1968, made significant improvements. Meanwhile, a counterculture movement grew, which was fueled by opposition to the Vietnam War, the Black Power movement, and the sexual revolution. The women's movement in the U.S. broadened the debate on women's rights and made gender equality a major social goal. The 1960s Sexual Revolution liberalized American attitudes to sexuality; the 1969 Stonewall riots in New York City marked the beginning of the fledgling gay rights movement.
The United States supported Israel during the Yom Kippur War; in response, the country faced an oil embargo from OPEC nations, sparking the 1973 oil crisis. After a surge in female labor participation around the 1970s, by 1985, the majority of women aged 16 and over were employed. The 1970s and early 1980s also saw the onset of stagflation. The presidency of Richard Nixon saw the American withdrawal from Vietnam but also the Watergate scandal which led to a decline in public trust of government.
After his election in 1980 President Ronald Reagan responded to economic stagnation with neoliberal reforms and initiated the more aggressive rollback strategy towards the Soviet Union. During Reagan's presidency, the federal debt held by the public nearly tripled in nominal terms, from $738 billion to $2.1 trillion. This led to the United States moving from the world's largest international creditor to the world's largest debtor nation. The dissolution of the Soviet Union in 1991 ended the Cold War, ensuring a global unipolarity in which the U.S. was unchallenged as the world's dominant superpower.
Fearing the spread of regional international instability from the Iraqi invasion of Kuwait, in August 1991, President George H. W. Bush launched and led the Gulf War against Iraq, expelling Iraqi forces and restoring the Kuwaiti monarchy. Beginning in 1994, the U.S. signed the North American Free Trade Agreement (NAFTA), causing trade among the U.S., Canada, and Mexico to soar. Due to the dot-com boom, stable monetary policy, and reduced social welfare spending, the 1990s saw the longest economic expansion in modern U.S. history.
On September 11, 2001, al-Qaeda terrorist hijackers flew passenger planes into the World Trade Center in New York City and the Pentagon near Washington, D.C., killing nearly 3,000 people. In response, President George W. Bush launched the War on Terror, which included a nearly 20-year war in Afghanistan from 2001 to 2021 and the 2003–2011 Iraq War. Government policy designed to promote affordable housing, widespread failures in corporate and regulatory governance, and historically low interest rates set by the Federal Reserve led to a housing bubble in 2006. This culminated in the financial crisis of 2007–2008 and the Great Recession, the nation's largest economic contraction since the Great Depression.
Barack Obama, the first multiracial president with African-American ancestry, was elected in 2008 amid the financial crisis. By the end of his second term, the stock market, median household income and net worth, and the number of persons with jobs were all at record levels, while the unemployment rate was well below the historical average. His signature legislative accomplishment was the Affordable Care Act (ACA), popularly known as "Obamacare". It represented the U.S. healthcare system's most significant regulatory overhaul and expansion of coverage since Medicare in 1965. As a result, the uninsured share of the population was cut in half, while the number of newly insured Americans was estimated to be between 20 and 24 million. After Obama served two terms, Republican Donald Trump was elected as the 45th president in 2016. His election is viewed as one of the biggest political upsets in American history. Trump held office through the first waves of the COVID-19 pandemic and the resulting COVID-19 recession starting in 2020 that exceeded even the Great Recession earlier in the century.
The early 2020s saw the country become more divided, with various social issues sparking debate and protest. The murder of George Floyd in 2020 led to widespread civil unrest in urban centers and a national debate about police brutality and lingering institutional racism. The nationwide increase in the frequency of instances and number of deaths related to mass shootings added to the societal tensions. On January 6, 2021, supporters of the outgoing president, Trump, stormed the U.S. Capitol in an unsuccessful effort to disrupt the Electoral College vote count that would confirm Democrat Joe Biden as the 46th president. In 2022, the Supreme Court ruled that there is no constitutional right to an abortion, causing another wave of protests across the country and stoking international reactions as well. Despite these divisions, the country has remained unified against Russia after Vladimir Putin's 2022 invasion of Ukraine, with politicians and individuals across the political spectrum supporting arms shipments to Ukraine and many large American corporations pulling out of Russia and Belarus altogether.
The 48 contiguous states and the District of Columbia occupy a combined area of 3,119,885 square miles (8,080,470 km2). Of this area, 2,959,064 square miles (7,663,940 km2) is contiguous land, composing 83.65% of total U.S. land area. About 15% is occupied by Alaska, a state in northwestern North America, with the remainder in Hawaii, a state and archipelago in the central Pacific, and the five populated but unincorporated insular territories of Puerto Rico, American Samoa, Guam, the Northern Mariana Islands, and the U.S. Virgin Islands. Measured by only land area, the United States is third in size behind Russia and China, and just ahead of Canada.
The United States is the world's third- or fourth-largest nation by total area (land and water), ranking behind Russia and Canada and nearly equal to China. The ranking varies depending on how two territories disputed by China and India are counted, and how the total size of the United States is measured.[b]
The coastal plain of the Atlantic seaboard gives way further inland to deciduous forests and the rolling hills of the Piedmont. The Appalachian Mountains and the Adirondack massif divide the eastern seaboard from the Great Lakes and the grasslands of the Midwest. The Mississippi–Missouri River, the world's fourth longest river system, runs mainly north–south through the heart of the country. The flat, fertile prairie of the Great Plains stretches to the west, interrupted by a highland region in the southeast.
The Rocky Mountains, west of the Great Plains, extend north to south across the country, peaking at over 14,000 feet (4,300 m) in Colorado. Farther west are the rocky Great Basin and deserts such as the Chihuahua, Sonoran, and Mojave. The Sierra Nevada and Cascade mountain ranges run close to the Pacific coast, both ranges also reaching altitudes higher than 14,000 feet (4,300 m). The lowest and highest points in the contiguous United States are in the state of California, and only about 84 miles (135 km) apart. At an elevation of 20,310 feet (6,190.5 m), Alaska's Denali is the highest peak in the country and in North America. Active volcanoes are common throughout Alaska's Alexander and Aleutian Islands, and Hawaii consists of volcanic islands. The supervolcano underlying Yellowstone National Park in the Rockies is the continent's largest volcanic feature.
The United States, with its large size and geographic variety, includes most climate types. To the east of the 100th meridian, the climate ranges from humid continental in the north to humid subtropical in the south.
The Great Plains west of the 100th meridian are semi-arid. Many mountainous areas of the American West have an alpine climate. The climate is arid in the Great Basin, desert in the Southwest, Mediterranean in coastal California, and oceanic in coastal Oregon and Washington and southern Alaska. Most of Alaska is subarctic or polar. Hawaii and the southern tip of Florida are tropical, as well as its territories in the Caribbean and the Pacific.
States bordering the Gulf of Mexico are prone to hurricanes, and most of the world's tornadoes occur in the country, mainly in Tornado Alley areas in the Midwest and South. Overall, the United States receives more high-impact extreme weather incidents than any other country in the world.
Extreme weather has become more frequent in the U.S., with three times the number of reported heat waves as in the 1960s. Of the ten warmest years ever recorded in the 48 contiguous states, eight have occurred since 1998. In the American Southwest, droughts have become more persistent and more severe.
Biodiversity and conservation
The U.S. is one of 17 megadiverse countries containing large numbers of endemic species: about 17,000 species of vascular plants occur in the contiguous United States and Alaska, and more than 1,800 species of flowering plants are found in Hawaii, few of which occur on the mainland. The United States is home to 428 mammal species, 784 birds, 311 reptiles, and 295 amphibians, and 91,000 insect species.
There are 63 national parks and hundreds of other federally managed parks, forests, and wilderness areas, which are managed by the National Park Service. Altogether, the government owns about 28% of the country's land area, mostly in the western states. Most of this land is protected, though some is leased for oil and gas drilling, mining, logging, or cattle ranching, and about .86% is used for military purposes.
Environmental issues include debates on oil and nuclear energy, dealing with air and water pollution, the economic costs of protecting wildlife, logging and deforestation, and climate change. The most prominent environmental agency is the Environmental Protection Agency (EPA), created by presidential order in 1970. The idea of wilderness has shaped the management of public lands since 1964, with the Wilderness Act. The Endangered Species Act of 1973 is intended to protect threatened and endangered species and their habitats, which are monitored by the United States Fish and Wildlife Service.
As of 2020, the U.S. ranked 24th among nations in the Environmental Performance Index. The country joined the Paris Agreement on climate change in 2016, and has many other environmental commitments. It withdrew from the Paris Agreement in 2020 but rejoined it in 2021.
Government and politics
The United States is a federal republic of 50 states, a federal district, five territories and several uninhabited island possessions. It is the world's oldest surviving federation. It is a federal republic and a representative democracy "in which majority rule is tempered by minority rights protected by law." In the American federal system, sovereignty is shared between two levels of government: federal and state. Citizens of the states are also governed by local governments, which are administrative divisions of the states. The territories are administrative divisions of the federal government.
The U.S. Constitution serves as the country's supreme legal document. The Constitution establishes the structure and responsibilities of the federal government and its relationship with the individual states. The Constitution has been amended 27 times; the first ten amendments (Bill of Rights) and the Fourteenth Amendment form the central basis of Americans' individual rights. All laws and governmental procedures are subject to judicial review, and any law can be voided if the courts determine that it violates the Constitution. The principle of judicial review, not explicitly mentioned in the Constitution, was established by the Supreme Court in Marbury v. Madison (1803).
The United States has operated under a two-party system for most of its history. In American political culture, the center-right Republican Party is considered "conservative" and the center-left Democratic Party is considered "liberal". On Transparency International's 2019 Corruption Perceptions Index, its public sector position deteriorated from a score of 76 in 2015 to 69 in 2019. In 2021, the U.S. ranked 26th on the Democracy Index, and is described as a "flawed democracy".
- Legislative: The bicameral Congress, made up of the Senate and the House of Representatives, makes federal law, declares war, approves treaties, has the power of the purse, and has the power of impeachment, by which it can remove sitting members of the federal government.
- Executive: The president is the commander-in-chief of the military, can veto legislative bills before they become law (subject to congressional override), and appoints the members of the Cabinet (subject to Senate approval) and other officers, who administer and enforce federal laws and policies.
- Judicial: The Supreme Court and lower federal courts, whose judges are appointed by the president with Senate approval, interpret laws and overturn those they find unconstitutional.
The lower house, the House of Representatives, has 435 voting members, each representing a congressional district for a two-year term. House seats are apportioned among the states by population. Each state then draws single-member districts to conform with the census apportionment. The District of Columbia and the five major U.S. territories each have one member of Congress—these members are not allowed to vote.
The upper house, the Senate, has 100 members with each state having two senators, elected at large to six-year terms; one-third of Senate seats are up for election every two years. The District of Columbia and the five major U.S. territories do not have senators. The Senate is unique among upper houses in being the most prestigious and powerful portion of the country's bicameral system; political scientists have frequently labeled it the "most powerful upper house" of any government.
The president serves a four-year term and may be elected to the office no more than twice. The president is not elected by direct vote, but by an indirect electoral college system in which the determining votes are apportioned to the states and the District of Columbia. The Supreme Court, led by the chief justice of the United States, has nine members, who serve for life.
Each of the 50 states holds jurisdiction over a geographic territory, where it shares sovereignty with the federal government. They are subdivided into counties or county equivalents, and further divided into municipalities. The District of Columbia is a federal district that contains the capital of the United States, the city of Washington. Each state has the amount presidential electors equal to the number of their representatives plus senators in Congress, and the District of Columbia has three electors. Territories of the United States do not have presidential electors, therefore people there cannot vote for the president.
Citizenship is granted at birth in all states, the District of Columbia, and all major U.S. territories except American Samoa.[l] The United States observes limited tribal sovereignty of the American Indian nations, like states' sovereignty. American Indians are U.S. citizens and tribal lands are subject to the jurisdiction of the U.S. Congress and the federal courts. Like the states, tribes have some autonomy restrictions. They are prohibited from making war, engaging in their own foreign relations, and printing or issuing independent currency. Indian reservations are usually contained within one state, but there are 12 reservations that cross state boundaries.
The United States has an established structure of foreign relations, and it had the world's second-largest diplomatic corps in 2019. It is a permanent member of the United Nations Security Council, and home to the United Nations headquarters. The United States is also a member of the G7, G20, and OECD intergovernmental organizations. Almost all countries have embassies and many have consulates (official representatives) in the country. Likewise, nearly all nations host formal diplomatic missions with United States, except Iran, North Korea, and Bhutan. Though Taiwan does not have formal diplomatic relations with the U.S., it maintains close, if unofficial, relations. The United States also regularly supplies Taiwan with military equipment.
The United States has a "Special Relationship" with the United Kingdom and strong ties with Canada, Australia, New Zealand, the Philippines, Japan, South Korea, Israel, and several European Union countries (France, Italy, Germany, Spain, and Poland). The U.S. works closely with its NATO allies on military and national security issues, and with nations in the Americas through the Organization of American States and the United States–Mexico–Canada Free Trade Agreement. In South America, Colombia is traditionally considered to be the closest ally of the United States. The U.S. exercises full international defense authority and responsibility for Micronesia, the Marshall Islands and Palau through the Compact of Free Association. Since the 2022 Russian invasion of Ukraine, the U.S. has become a key ally of Ukraine since Russia annexed Crimea in 2014 and began an invasion of Ukraine in 2022, significantly deteriorating relations with Russia in the process. The U.S. has also experienced a deterioration of relations with China and grown closer to Taiwan.
The president is the commander-in-chief of the United States Armed Forces and appoints its leaders, the secretary of defense and the Joint Chiefs of Staff. The Department of Defense, which is headquartered at the Pentagon near Washington, D.C., administers five of the six service branches, which are made up of the Army, Marine Corps, Navy, Air Force, and Space Force. The Coast Guard is administered by the Department of Homeland Security in peacetime and can be transferred to the Department of the Navy in wartime. The United States spent $649 billion on its military in 2019, 36% of global military spending. At 4.7% of GDP, the percentage was the second-highest among all countries, after Saudi Arabia. It also has more than 40% of the world's nuclear weapons, the second-largest after Russia.
In 2019, all six branches of the U.S. Armed Forces reported 1.4 million personnel on active duty. The Reserves and National Guard brought the total number of troops to 2.3 million. The Department of Defense also employed about 700,000 civilians, not including contractors. Military service in the United States is voluntary, although conscription may occur in wartime through the Selective Service System. The United States has the third-largest combined armed forces in the world, behind the Chinese People's Liberation Army and Indian Armed Forces.
Today, American forces can be rapidly deployed by the Air Force's large fleet of transport aircraft, the Navy's 11 active aircraft carriers, and Marine expeditionary units at sea with the Navy, and Army's XVIII Airborne Corps and 75th Ranger Regiment deployed by Air Force transport aircraft. The Air Force can strike targets across the globe through its fleet of strategic bombers, maintains the air defense across the United States, and provides close air support to Army and Marine Corps ground forces.
The Space Force operates the Global Positioning System, operates the Eastern and Western Ranges for all space launches, and operates the United States's Space Surveillance and Missile Warning networks. The military operates about 800 bases and facilities abroad, and maintains deployments greater than 100 active duty personnel in 25 foreign countries.
Law enforcement and crime
There are about 18,000 U.S. police agencies from local to federal level in the United States. Law in the United States is mainly enforced by local police departments and sheriff's offices. The state police provides broader services, and federal agencies such as the Federal Bureau of Investigation (FBI) and the U.S. Marshals Service have specialized duties, such as protecting civil rights, national security and enforcing U.S. federal courts' rulings and federal laws. State courts conduct most civil and criminal trials, and federal courts handle designated crimes and appeals from the state criminal courts.
As of 2020[update], the United States has an intentional homicide rate of 7 per 100,000 people. A cross-sectional analysis of the World Health Organization Mortality Database from 2010 showed that United States homicide rates "were 7.0 times higher than in other high-income countries, driven by a gun homicide rate that was 25.2 times higher."
The United States has the highest documented incarceration rate and largest prison population in the world. In 2019, the total prison population for those sentenced to more than a year is 1,430,800, corresponding to a ratio of 419 per 100,000 residents and the lowest since 1995. Some estimates place that number higher, such Prison Policy Initiative's 2.3 million. Various states have attempted to reduce their prison populations via government policies and grassroots initiatives.
Although most nations have abolished capital punishment, it is sanctioned in the United States for certain federal and military crimes, and in 27 states out of 50 and in one territory. Several of these states have moratoriums on carrying out the penalty, each imposed by the state's governor. Since 1977, there have been more than 1,500 executions, giving the U.S. the sixth-highest number of executions in the world, following China, Iran, Saudi Arabia, Iraq, and Egypt. However, the number is trended down nationally, with several states recently abolishing the penalty.
According to the International Monetary Fund, the U.S. gross domestic product (GDP) of $22.7 trillion constitutes 24% of the gross world product at market exchange rates and over 16% of the gross world product at purchasing power parity (PPP). From 1983 to 2008, U.S. real compounded annual GDP growth was 3.3%, compared to a 2.3% weighted average for the rest of the G7. The country ranks fifth in the world in nominal GDP per capita and seventh in GDP per capita at PPP. The country has been the world's largest economy since at least 1900.
The United States is the most technologically powerful and innovative nation, especially in artificial intelligence, computers, pharmaceuticals, and medical, aerospace, and military equipment. The nation's economy is fueled by abundant natural resources, a well-developed infrastructure, and high productivity. It has the second-highest total-estimated value of natural resources, valued at US$ 44.98 trillion in 2019, although sources differ on their estimates. Americans have the highest average household and employee income among OECD member states. In 2013, they had the sixth-highest median household income, down from fourth-highest in 2010.
The U.S. dollar is the currency most used in international transactions and is the world's foremost reserve currency, backed by its economy, its military, the petrodollar system and its linked eurodollar and large U.S. treasuries market. Several countries use it as their official currency and in others it is the de facto currency. The New York Stock Exchange and Nasdaq are the world's largest stock exchanges by market capitalization and trade volume.
The largest U.S. trading partners are China, the European Union, Canada, Mexico, India, Japan, South Korea, the United Kingdom, and Taiwan. The U.S. is the world's largest importer and the second-largest exporter. It has free trade agreements with several countries, including the USMCA. The U.S. ranked second in the Global Competitiveness Report in 2019, after Singapore. Of the world's 500 largest companies, 124 are headquartered in the U.S.
While its economy has reached a post-industrial level of development, the United States remains an industrial power. It has a smaller welfare state and redistributes less income through government action than most other high-income countries. The United States ranked the 41st highest in income inequality among 156 countries in 2017, and the highest compared to the rest of the developed world. As of January 1, 2023, the United States had a national debt of $31.4 trillion.
Income and poverty
At $46,625 USD in 2021, American citizens have the highest median income in the world. Despite the fact that they only account for 4.24% of the global population, they collectively possess 30.2% of the world's total wealth as of 2021, the largest percentage of any country. The U.S. also ranks first in the number of dollar billionaires and millionaires in the world, with 724 billionaires (as of 2021) and nearly 22 million millionaires (2021).
Wealth in the United States is highly concentrated; the richest 10% of the adult population own 72% of the country's household wealth, while the bottom 50% own just 2%. Income inequality in the U.S. remains at record highs, with the top fifth of earners taking home more than half of all income and giving the U.S. one of the widest income distributions among OECD members. The United States is the only advanced economy that does not guarantee its workers paid vacation and is one of a few countries in the world without paid family leave as a legal right. The United States also has a higher percentage of low-income workers than almost any other developed nation, largely because of a weak collective bargaining system and lack of government support for at-risk workers.
There were about 567,715 sheltered and unsheltered homeless persons in the U.S. in January 2019, with almost two-thirds staying in an emergency shelter or transitional housing program. Attempts to combat homelessness include the Section 8 housing voucher program and implementation of the Housing First strategy across all levels of government.
In 2011, 16.7 million children lived in food-insecure households, about 35% more than 2007 levels, though only 845,000 U.S. children (1.1%) saw reduced food intake or disrupted eating patterns at some point during the year, and most cases were not chronic. As of June 2018,[update] 40 million people, roughly 12.7% of the U.S. population, were living in poverty, including 13.3 million children. Of those impoverished, 18.5 million live in "deep poverty", family income below one-half of the federal government's poverty threshold.
Science, technology, and energy
The United States has been a leader in technological innovation since the late 19th century and scientific research since the mid-20th century. Methods for producing interchangeable parts and the establishment of a machine tool industry enabled the U.S. to have large-scale manufacturing of sewing machines, bicycles, and other items in the late 19th century. In the early 20th century, factory electrification, the introduction of the assembly line, and other labor-saving techniques created the system of mass production. In the 21st century, approximately two-thirds of research and development funding comes from the private sector. In 2020, the United States was the country with the second-highest number of published scientific papers and second most patents granted, both after China. In 2021, the United States launched a total of 51 spaceflights. (China reported 55.) The U.S. had 2,944 active satellites in space in December 2021, the highest number of any country.
In 1876, Alexander Graham Bell was awarded the first U.S. patent for the telephone. Thomas Edison's research laboratory developed the phonograph, the first long-lasting light bulb, and the first viable movie camera. The Wright brothers in 1903 made the first sustained and controlled heavier-than-air powered flight, and the automobile companies of Ransom E. Olds and Henry Ford popularized the assembly line in the early 20th century. The rise of fascism and Nazism in the 1920s and 30s led many European scientists, such as Albert Einstein, Enrico Fermi, and John von Neumann, to immigrate to the United States. During World War II, the Manhattan Project developed nuclear weapons, ushering in the Atomic Age. During the Cold War, competition for superior missile capability ushered in the Space Race between the U.S. and Soviet Union. The invention of the transistor in the 1950s, a key component in almost all modern electronics, led to the development of microprocessors, software, personal computers and the Internet. In 2022, the United States ranked 2nd in the Global Innovation Index.
As of 2019[update], the United States receives approximately 80% of its energy from fossil fuels. In 2019, the largest source of the country's energy came from petroleum (36.6%), followed by natural gas (32%), coal (11.4%), renewable sources (11.4%) and nuclear power (8.4%). Americans constitute less than 5% of the world's population, but consume 17% of the world's energy. They account for about 25% of the world's petroleum consumption, while producing only 6% of the world's annual petroleum supply. The U.S. ranks as second-highest emitter of greenhouse gases, exceeded only by China.
The United States's rail network, nearly all standard gauge, is the longest in the world, and exceeds 293,564 km (182,400 mi). It handles mostly freight, with intercity passenger service provided by Amtrak to all but four states. The country's inland waterways are the world's fifth-longest, and total 41,009 km (25,482 mi).
Personal transportation is dominated by automobiles, which operate on a network of 4 million miles (6.4 million kilometers) of public roads. The United States has the world's second-largest automobile market, and has the highest vehicle ownership per capita in the world, with 816.4 vehicles per 1,000 Americans (2014). In 2017, there were 255 million non-two wheel motor vehicles, or about 910 vehicles per 1,000 people.
The civil airline industry is entirely privately owned and has been largely deregulated since 1978, while most major airports are publicly owned. The three largest airlines in the world by passengers carried are U.S.-based; American Airlines is number one after its 2013 acquisition by US Airways. Of the world's 50 busiest passenger airports, 16 are in the United States, including the busiest, Hartsfield–Jackson Atlanta International Airport. Of the fifty busiest container ports, four are located in the United States, of which the busiest is the Port of Los Angeles.
|U.S. Decennial Census|
The U.S. Census Bureau reported 331,449,281 residents as of April 1, 2020,[m] making the United States the third most populous nation in the world, after China and India. According to the Bureau's U.S. Population Clock, on January 28, 2021, the U.S. population had a net gain of one person every 100 seconds, or about 864 people per day. In 2018, 52% of Americans age 15 and over were married, 6% were widowed, 10% were divorced, and 32% had never been married. In 2020, the U.S. had a total fertility rate stood at 1.64 children per woman and the world's highest rate (23%) of children living in single-parent households.
The United States of America has a diverse population; 37 ancestry groups have more than one million members. White Americans with ancestry from Europe, the Middle East or North Africa, form the largest racial and ethnic group at 57.8% of the United States population. Hispanic and Latino Americans form the second-largest group and are 18.7% of the United States population. African Americans constitute the nation's third-largest ancestry group and are 12.1% of the total United States population. Asian Americans are the country's fourth-largest group, composing 5.9% of the United States population, while the country's 3.7 million Native Americans account for about 1%. In 2020, the median age of the United States population was 38.5 years.
In 2018, there were almost 90 million immigrants and U.S.-born children of immigrants in the United States, accounting for 28% of the overall U.S. population. In 2017, out of the U.S. foreign-born population, some 45% (20.7 million) were naturalized citizens, 27% (12.3 million) were lawful permanent residents, 6% (2.2 million) were temporary lawful residents, and 23% (10.5 million) were unauthorized immigrants. The United States led the world in refugee resettlement for decades, admitting more refugees than the rest of the world combined.
English (specifically, American English) is the de facto national language of the United States. Although there is no official language at the federal level, some laws—such as U.S. naturalization requirements—standardize English, and most states have declared English as the official language. Three states and four U.S. territories have recognized local or indigenous languages in addition to English, including Hawaii (Hawaiian), Alaska (twenty Native languages),[n] South Dakota (Sioux), American Samoa (Samoan), Puerto Rico (Spanish), Guam (Chamorro), and the Northern Mariana Islands (Carolinian and Chamorro). In Puerto Rico, Spanish is more widely spoken than English.
According to the American Community Survey, in 2010 some 229 million people (out of the total U.S. population of 308 million) spoke only English at home. More than 37 million spoke Spanish at home, making it the second most commonly used language in the United States. Other languages spoken at home by one million people or more include Chinese (2.8 million), Tagalog (1.6 million), Vietnamese (1.4 million), French (1.3 million), Korean (1.1 million), and German (1 million).
The most widely taught foreign languages in the United States, in terms of enrollment numbers from kindergarten through university undergraduate education, are Spanish (around 7.2 million students), French (1.5 million), and German (500,000). Other commonly taught languages include Latin, Japanese, American Sign Language, Italian, and Chinese.
A large variety of faiths have historically flourished within the country. According to the World Values Survey in 2017, the United States is more secular than the median country; they ranked the United States the 32nd least religious country in the world. Until the 1990s, the country was a substantial outlier among other highly developed countries: uniquely combining a high level of religiosity and wealth, although this has lessened significantly since then. Studies during the early 2020s found that about 81% of Americans believe in some conception of God, 45% report praying on a daily basis, 41% report that religion plays a very important role in their lives, and 31% report attending religious services weekly or near weekly. According to Gallup in December 2022, 58% of Americans report "seldom" or "never" attending religious services. According to the Institute for Family Studies in 2022, around 28% of Americans attended at least once or twice a month.
In a 2020 survey, about 64% of adults in the United States identified themselves as Christians making it the country with the largest Christian population. Protestantism is the largest Christian religious grouping in the United States, accounting for around a third of all Americans. In the so-called Bible Belt, located primarily within the Southern United States, socially conservative evangelical Protestantism plays a significant role culturally. By contrast, religion plays the least important role in New England and the Western United States.
Around 30% of Americans describe themselves as having no religion. Membership in a house of worship fell from 70% in 1999 to 47% in 2020, much of the decline related to the number of Americans expressing no religious preference. Membership also fell among those who identified with a specific religious group. According to Gallup, trust in "the church or organized religion" has declined significantly since the 1970s.
About 82% of Americans live in urban areas, including suburbs; about half of those reside in cities with populations over 50,000. In 2008, 273 incorporated municipalities had populations over 100,000, nine cities had more than one million residents, and four cities (New York City, Los Angeles, Chicago, and Houston) had populations exceeding two million. Many U.S. metropolitan populations are growing rapidly, particularly in the South and West.
|2||Los Angeles||West||12,997,353||12||Riverside–San Bernardino||West||4,653,105|
|6||Washington, D.C.||South||6,356,434||16||Minneapolis–Saint Paul||Midwest||3,690,512|
American public education is operated by state and local governments and regulated by the United States Department of Education through restrictions on federal grants. In most states, children are required to attend school from the age of five or six (beginning with kindergarten or first grade) until they turn 18 (generally bringing them through twelfth grade, the end of high school); some states allow students to leave school at 16 or 17. Of Americans 25 and older, 84.6% graduated from high school, 52.6% attended some college, 27.2% earned a bachelor's degree, and 9.6% earned graduate degrees. The basic literacy rate is approximately 99%.
The United States has many private and public institutions of higher education. The majority of the world's top public and private universities, as listed by various ranking organizations, are in the United States. There are also local community colleges with generally more open admission policies, shorter academic programs, and lower tuition. The U.S. spends more on education per student than any nation in the world, spending an average of $12,794 per year on public elementary and secondary school students in the 2016–2017 school year. As for public expenditures on higher education, the U.S. spends more per student than the OECD average, and more than all nations in combined public and private spending. Despite some student loan forgiveness programs in place, student loan debt has increased by 102% in the last decade, and exceeded 1.7 trillion dollars as of 2022.
In a preliminary report, the Centers for Disease Control and Prevention (CDC) announced that U.S. life expectancy at birth had dropped to 76.4 years in 2021 (73.2 years for men and 79.1 years for women), down 0.9 years from 2020. This was the second year of overall decline, and the chief causes listed were the COVID-19 pandemic, accidents, drug overdoses, heart and liver disease, and suicides. Life expectancy was highest among Asians and Hispanics and lowest among Blacks and American Indian–Alaskan Native (AIAN) peoples. Starting in 1998, the average life expectancy in the U.S. fell behind that of other wealthy industrialized countries, and Americans' "health disadvantage" gap has been increasing ever since. The U.S. also has one of the highest suicide rates among high-income countries, and approximately one-third of the U.S. adult population is obese and another third is overweight.
In 2010, coronary artery disease, lung cancer, stroke, chronic obstructive pulmonary diseases, and traffic collisions caused the most years of life lost in the U.S. Low back pain, depression, musculoskeletal disorders, neck pain, and anxiety caused the most years lost to disability. The most harmful risk factors were poor diet, tobacco smoking, obesity, high blood pressure, high blood sugar, physical inactivity, and alcohol consumption. Alzheimer's disease, substance use disorders, kidney disease, cancer, and falls caused the most additional years of life lost over their age-adjusted 1990 per-capita rates. Teenage pregnancy and abortion rates in the U.S. are substantially higher than in other Western nations, especially among blacks and Hispanics.
The U.S. health care system far outspends that of any other nation, measured both in per capita spending and as a percentage of GDP but attains worse healthcare outcomes when compared to peer nations. The United States is the only developed nation without a system of universal health care, and a significant proportion of the population that does not carry health insurance. The U.S., however, is a global leader in medical innovation, measured either in terms of revenue or the number of new drugs and devices introduced.
Government-funded health care coverage for the poor (Medicaid, established in 1965) and for those age 65 and older (Medicare, begun in 1966) is available to Americans who meet the programs' income or age qualifications. In 2010, former President Obama passed the Patient Protection and Affordable Care Act or ACA,[o] which the CDC said that the law roughly halved the uninsured share of the population and multiple studies have concluded that ACA had reduced the mortality of enrollees. However, its legacy remains controversial.
Culture and society
Americans have traditionally been characterized by a strong work ethic, competitiveness, and individualism, as well as a unifying belief in an "American creed" emphasizing liberty, social equality, property rights, democracy, equality under the law, and a preference for limited government. Americans are extremely charitable by global standards: according to a 2016 study by the Charities Aid Foundation, Americans donated 1.44% of total GDP to charity, the highest in the world by a large margin. The United States is home to a wide variety of ethnic groups, traditions, and values, and exerts major cultural influence on a global scale. The country has been described as a society "built on a universalistic cultural frame rooted in the natural laws of science and human rights."
The Declaration of Independence has become a well-known statement on human rights, particularly its second sentence: "We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness." Stephen Lucas called it "one of the best-known sentences in the English language", with historian Joseph Ellis writing that the document contains "the most potent and consequential words in American history". The passage has since came to represent a moral standard to which the United States should strive. This view was notably promoted by Lincoln, who considered it to be the foundation of his political philosophy and argued that it is a statement of principles through which the Constitution should be interpreted.: 126
Aside from the Native American, Native Hawaiian, and Native Alaskan populations, nearly all Americans or their ancestors immigrated or were imported as slaves within the past five centuries. Mainstream American culture is a Western culture largely derived from the traditions of European immigrants with influences from many other sources, such as traditions brought by slaves from Africa. More recent immigration from Asia and especially Latin America has added to a cultural mix that has been described as a homogenizing melting pot, and a heterogeneous salad bowl, with immigrants contributing to, and often assimilating into, mainstream American culture. Nevertheless, there is a high degree of social inequality related to race and wealth. The American Dream, or the perception that Americans enjoy high social mobility, plays a key role in attracting immigrants. Whether this perception is accurate has been a topic of debate. While mainstream culture holds that the United States is a classless society, scholars identify significant differences between the country's social classes, affecting socialization, language, and values.
In the modern day, the country is considered to have permissive attitudes surrounding human sexuality. Public opinion and law surrounding LGBT rights has changed significantly since the late 1980s. A late 2022 Grinnell College National Poll found that 74% of Americans agree that same-sex marriage should be a guaranteed right while 13% disagree.
Literature and visual arts
In the 18th and early 19th centuries, American art and literature took most of their cues from Europe, contributing to Western culture. Writers such as Washington Irving, Nathaniel Hawthorne, Edgar Allan Poe, and Henry David Thoreau established a distinctive American literary voice by the middle of the 19th century. Mark Twain and poet Walt Whitman were major figures in the century's second half; Emily Dickinson, virtually unknown during her lifetime, is recognized as an essential American poet.
A work seen as capturing fundamental aspects of the national experience and character—such as Herman Melville's Moby-Dick (1851), Twain's The Adventures of Huckleberry Finn (1885), F. Scott Fitzgerald's The Great Gatsby (1925) and Harper Lee's To Kill a Mockingbird (1960)—may be dubbed the "Great American Novel."
Thirteen U.S. citizens have won the Nobel Prize in Literature. William Faulkner, Ernest Hemingway and John Steinbeck are often named among the most influential writers of the 20th century. The Beat Generation writers opened up new literary approaches, as have postmodernist authors such as John Barth, Thomas Pynchon, and Don DeLillo.
In the visual arts, the Hudson River School was a mid-19th-century movement in the tradition of European naturalism. The 1913 Armory Show in New York City, an exhibition of European modernist art, shocked the public and transformed the U.S. art scene. Georgia O'Keeffe, Marsden Hartley, and others experimented with new, individualistic styles.
Major artistic movements such as the abstract expressionism of Jackson Pollock and Willem de Kooning and the pop art of Andy Warhol and Roy Lichtenstein developed largely in the United States. The tide of modernism and then postmodernism has brought fame to American architects such as Frank Lloyd Wright, Philip Johnson, and Frank Gehry. Americans have long been important in the modern artistic medium of photography, with major photographers including Alfred Stieglitz, Edward Steichen, Edward Weston, and Ansel Adams.
Cinema and theater
Hollywood, a northern district of Los Angeles, California, is the leader in motion picture production and the most recognizable movie industry in the world. The major film studios of the United States are the primary source of the most commercially successful and most ticket selling movies in the world.
The world's first commercial motion picture exhibition was given in New York City in 1894, using the Kinetoscope. Since the early 20th century, the U.S. film industry has largely been based in and around Hollywood, although in the 21st century an increasing number of films are not made there, and film companies have been subject to the forces of globalization. The Academy Awards, popularly known as the Oscars, have been held annually by the Academy of Motion Picture Arts and Sciences since 1929, and the Golden Globe Awards have been held annually since January 1944.
Director D. W. Griffith, an American filmmaker during the silent film period, was central to the development of film grammar, and producer/entrepreneur Walt Disney was a leader in both animated film and movie merchandising. Directors such as John Ford redefined the image of the American Old West, and, like others such as John Huston, broadened the possibilities of cinema with location shooting. The industry enjoyed its golden years, in what is commonly referred to as the "Golden Age of Hollywood", from the early sound period until the early 1960s, with screen actors such as John Wayne and Marilyn Monroe becoming iconic figures. In the 1970s, "New Hollywood" or the "Hollywood Renaissance" was defined by grittier films influenced by French and Italian realist pictures of the post-war period.
Theater in the United States derives from the old European theatrical tradition and has been heavily influenced by the British theater. The central hub of the American theater scene has been Manhattan, with its divisions of Broadway, off-Broadway, and off-off-Broadway. Many movie and television stars have gotten their big break working in New York productions. Outside New York City, many cities have professional regional or resident theater companies that produce their own seasons, with some works being produced regionally with hopes of eventually moving to New York. The biggest-budget theatrical productions are musicals. U.S. theater also has an active community theater culture, which relies mainly on local volunteers who may not be actively pursuing a theatrical career.
American folk music encompasses numerous music genres, variously known as traditional music, traditional folk music, contemporary folk music, or roots music. Many traditional songs have been sung within the same family or folk group for generations, and sometimes trace back to such origins as the British Isles, Mainland Europe, or Africa.
Among America's earliest composers was a man named William Billings who, born in Boston, composed patriotic hymns in the 1770s; Billings was a part of the First New England School, who dominated American music during its earliest stages. Anthony Heinrich was the most prominent composer before the Civil War. From the mid- to late 1800s, John Philip Sousa of the late Romantic era composed numerous military songs—particularly marches—and is regarded as one of America's greatest composers.
The rhythmic and lyrical styles of African-American music have significantly influenced American music at large, distinguishing it from European and African traditions. Elements from folk idioms such as the blues and what is known as old-time music were adopted and transformed into popular genres with global audiences. Jazz was developed by innovators such as Louis Armstrong and Duke Ellington early in the 20th century. Country music developed in the 1920s, and rhythm and blues in the 1940s.
Elvis Presley and Chuck Berry were among the pioneers of rock and roll in the mid-1950s. Rock bands such as Metallica, the Eagles, and Aerosmith are among the highest grossing in worldwide sales. In the 1960s, Bob Dylan emerged from the folk revival to become one of America's most celebrated songwriters. Mid-20th-century American pop stars such as Bing Crosby, Frank Sinatra, and Elvis Presley became global celebrities, as have artists of the late 20th century such as Michael Jackson, Prince, Madonna, Whitney Houston, and Mariah Carey.
The four major broadcasters in the U.S. are the National Broadcasting Company (NBC), Columbia Broadcasting System (CBS), American Broadcasting Company (ABC), and Fox Broadcasting Company (FOX). The four major broadcast television networks are all commercial entities. Cable television offers hundreds of channels catering to a variety of niches. As of 2021[update], about 83% of Americans over age 12 listen to broadcast radio, while about 41% listen to podcasts. As of September 30, 2014[update], there are 15,433 licensed full-power radio stations in the U.S. according to the U.S. Federal Communications Commission (FCC). Much of the public radio broadcasting is supplied by NPR, incorporated in February 1970 under the Public Broadcasting Act of 1967.
Well-known U.S. newspapers include The Wall Street Journal, The New York Times, and USA Today. More than 800 publications are produced in Spanish, the second most commonly used language in the United States behind English. With very few exceptions, all the newspapers in the U.S. are privately owned, either by large chains such as Gannett or McClatchy, which own dozens or even hundreds of newspapers; by small chains that own a handful of papers; or, in a situation that is increasingly rare, by individuals or families. Major cities often have alternative newspapers to complement the mainstream daily papers, such as New York City's The Village Voice or Los Angeles' LA Weekly. The five most popular websites used in the U.S. are Google, YouTube, Amazon, Yahoo, and Facebook.
The American video game industry is the world's 2nd largest by revenue. It generated $90 billion in annual economic output in 2020. Furthermore, the video game industry contributed $12.6 billion in federal, state, and municipal taxes annually. Some of the largest video game companies like Activision Blizzard, Xbox, Sony Interactive Entertainment, Rockstar Games, and Electronic Arts are based in the United States. Some of the most popular and best selling video games like The Elder Scrolls V: Skyrim, Call of Duty: Modern Warfare and Diablo III are made by American developers. The American video gaming business is still a significant employer. More than 143,000 individuals are employed directly and indirectly by video game companies throughout 50 states. The national compensation for direct workers is US$2.9 billion, or an average wage of US$121,000.
Early settlers were introduced by Native Americans to such indigenous, non-European foods as turkey, sweet potatoes, corn, squash, and maple syrup. They and later immigrants combined these with foods they had known, such as wheat flour, beef, and milk to create a distinctive American cuisine. Homegrown foods are part of a shared national menu on one of America's most popular holidays, Thanksgiving, when many Americans make or purchase traditional foods to celebrate the occasion.
The American fast food industry, the world's largest, pioneered the drive-through format in the 1940s. Characteristic American dishes such as apple pie, fried chicken, doughnuts, french fries, macaroni and cheese, ice cream, pizza, hamburgers, and hot dogs derive from the recipes of various immigrants. Mexican dishes such as burritos and tacos and pasta dishes freely adapted from Italian sources are widely consumed.
While most major U.S. sports such as baseball and American football have evolved out of European practices, basketball, volleyball, skateboarding, and snowboarding are American inventions, some of which have become popular worldwide. Lacrosse and surfing arose from Native American and Native Hawaiian activities that predate European contact. The market for professional sports in the United States is roughly $69 billion, roughly 50% larger than that of all of Europe, the Middle East, and Africa combined.
American football is by several measures the most popular spectator sport in the United States; the National Football League (NFL) has the highest average attendance of any sports league in the world, and the Super Bowl is watched by tens of millions globally. Baseball has been regarded as the U.S. national sport since the late 19th century, with Major League Baseball being the top league. Basketball and ice hockey are the country's next two most popular professional team sports, with the top leagues being the National Basketball Association and the National Hockey League. The most-watched individual sports in the U.S. are golf and auto racing, particularly NASCAR and IndyCar.
Eight Olympic Games have taken place in the United States. The 1904 Summer Olympics in St. Louis, Missouri, were the first-ever Olympic Games held outside of Europe. The Olympic Games will be held in the U.S. for a ninth time when Los Angeles hosts the 2028 Summer Olympics. As of 2021[update], the United States has won 2,629 medals at the Summer Olympic Games, more than any other country, and 330 in the Winter Olympic Games, the second most behind Norway. In soccer, the men's national soccer team qualified for eleven World Cups and the women's team has won the FIFA Women's World Cup four times. The United States hosted the 1994 FIFA World Cup and will host the 2026 FIFA World Cup along with Canada and Mexico. On the collegiate level, earnings for the member institutions exceed $1 billion annually, and college football and basketball attract large audiences, as the NCAA Final Four is one of the most watched sporting events.
- The historical and informal demonym Yankee has been applied to Americans, New Englanders, or northeasterners since the 18th century.
- At 3,531,900 sq mi (9,147,590 km2), the United States is the third-largest country in the world by land area, behind Russia and China. By total area (land and water), it is the third-largest behind Russia and Canada, if its coastal and territorial water areas are included. However, if only its internal waters are included (bays, sounds, rivers, lakes, and the Great Lakes), the U.S. is the fourth-largest, after Russia, Canada, and China.
Coastal/territorial waters included: 3,796,742 sq mi (9,833,517 km2)
Only internal waters included: 3,696,100 sq mi (9,572,900 km2)
- Excludes Puerto Rico and the other unincorporated islands because they are counted separately in U.S. census statistics.
- See Time in the United States for details about laws governing time zones in the United States.
- See Date and time notation in the United States.
- A single jurisdiction, the U.S. Virgin Islands, uses left-hand traffic.
- The five major territories are American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and the United States Virgin Islands. There are eleven smaller island areas without permanent populations: Baker Island, Howland Island, Jarvis Island, Johnston Atoll, Kingman Reef, Midway Atoll, and Palmyra Atoll. U.S. sovereignty over Bajo Nuevo Bank, Navassa Island, Serranilla Bank, and Wake Island is disputed.
- The United States has a maritime border with the British Virgin Islands, a British territory, since the BVI borders the U.S. Virgin Islands. BVI is a British Overseas Territory but itself is not a part of the United Kingdom. Puerto Rico has a maritime border with the Dominican Republic. American Samoa has a maritime border with the Cook Islands, maintained under the Cook Islands–United States Maritime Boundary Treaty. American Samoa also has maritime borders with independent Samoa and Niue.
- The U.S. Census Bureau provides a continuously updated but unofficial population clock in addition to its decennial census and annual population estimates: 
- New Hampshire, Massachusetts, Connecticut, Rhode Island, New York, New Jersey, Pennsylvania, Delaware, Maryland, Virginia, North Carolina, South Carolina, and Georgia
- John Adams, Thomas Jefferson, Benjamin Franklin, Roger Sherman, and Robert R. Livingston
- People born in American Samoa are non-citizen U.S. nationals unless one of their parents is a U.S. citizen. In 2019, a court ruled that American Samoans are U.S. citizens, but the litigation is ongoing.
- This figure, like most official data for the United States as a whole, excludes the five unincorporated territories (Puerto Rico, Guam, the U.S. Virgin Islands, American Samoa, and the Northern Mariana Islands) and minor island possessions.
- Inupiaq, Siberian Yupik, Central Alaskan Yup'ik, Alutiiq, Unanga (Aleut), Denaʼina, Deg Xinag, Holikachuk, Koyukon, Upper Kuskokwim, Gwichʼin, Tanana, Upper Tanana, Tanacross, Hän, Ahtna, Eyak, Tlingit, Haida, and Tsimshian
- Also known less formally as Obamacare
- 36 U.S.C. § 302
- "The Great Seal of the United States" (PDF). U.S. Department of State, Bureau of Public Affairs. 2003. Retrieved February 12, 2020.
- "An Act To make The Star-Spangled Banner the national anthem of the United States of America". H.R. 14, Act of March 3, 1931. 71st United States Congress.
- "2020 Census Illuminates Racial and Ethnic Composition of the Country". United States Census. Retrieved August 13, 2021.
- "Race and Ethnicity in the United States: 2010 Census and 2020 Census". United States Census. Retrieved August 13, 2021.
- "A Breakdown of 2020 Census Demographic Data". NPR. August 13, 2021.
- "About Three-in-Ten U.S. Adults Are Now Religiously Unaffiliated". Measuring Religion in Pew Research Center's American Trends Panel. Pew Research Center. December 14, 2021. Retrieved December 21, 2021.
- Compton's Pictured Encyclopedia and Fact-index: Ohio. 1963. p. 336.
- Areas of the 50 states and the District of Columbia but not Puerto Rico nor other island territories per "State Area Measurements and Internal Point Coordinates". Census.gov. August 2010. Retrieved March 31, 2020.
reflect base feature updates made in the MAF/TIGER database through August, 2010.
- "Surface water and surface water change". Organisation for Economic Co-operation and Development (OECD). 2015. Retrieved October 11, 2020.
- Bureau, US Census. "Growth in U.S. Population Shows Early Indication of Recovery Amid COVID-19 Pandemic". Census.gov. Retrieved December 24, 2022.
- "Census Bureau's 2020 Population Count". United States Census. Retrieved April 26, 2021. The 2020 census is as of April 1, 2020.
- "World Economic Outlook Database, October 2022". IMF.org. International Monetary Fund. October 2022. Retrieved October 11, 2022.
- Bureau, US Census. "Income and Poverty in the United States: 2020, Table A-3". Census.gov. Retrieved July 26, 2022.
- "Human Development Report 2021/2022" (PDF). United Nations Development Programme. September 8, 2022. Retrieved September 8, 2022.
- U.S. State Department, Common Core Document to U.N. Committee on Human Rights, December 30, 2011, Item 22, 27, 80. And U.S. General Accounting Office Report, U.S. Insular Areas: application of the U.S. Constitution Archived November 3, 2013, at the Wayback Machine, November 1997, pp. 1, 6, 39n. Both viewed April 6, 2016.
- "China". CIA World Factbook. Retrieved June 10, 2016.
- "United States". Encyclopædia Britannica. Archived from the original on December 19, 2013. Retrieved January 31, 2010.
- "United States Virgin Islands". Encyclopædia Britannica (Online ed.). Archived from the original on April 29, 2020. Retrieved July 3, 2020.
[...]which also contains its near neighbour, the British Virgin Islands.
- "United Kingdom Overseas Territories - Toponymic Information" (PDF). Present Committee on Geographic Names. Retrieved January 7, 2023. - Hosted on the Government of the United Kingdom website.
- "Puerto Rico". Encyclopædia Britannica (Online ed.). Archived from the original on July 2, 2020. Retrieved July 3, 2020.
- Anderson, Ewan W. (2003). International Boundaries: A Geopolitical Atlas. Routledge: New York. ISBN 9781579583750; OCLC 54061586
- Charney, Jonathan I., David A. Colson, Robert W. Smith. (2005). International Maritime Boundaries, 5 vols. Hotei Publishing: Leiden.
- "Pacific Maritime Boundaries". pacgeo.org. Archived from the original on July 31, 2020. Retrieved July 3, 2020.
- Sider 2007, p. 226.
- Szalay, Jessie (September 20, 2017). "Amerigo Vespucci: Facts, Biography & Naming of America". Live Science. Retrieved June 23, 2019.
- Jonathan Cohen. "The Naming of America: Fragments We've Shored Against Ourselves". Archived from the original on October 6, 2018. Retrieved February 3, 2014.
- DeLear, Byron (July 4, 2013) Who coined 'United States of America'? Mystery might have intriguing answer. "Historians have long tried to pinpoint exactly when the name 'United States of America' was first used and by whom ... This latest find comes in a letter that Stephen Moylan, Esq., wrote to Col. Joseph Reed from the Continental Army Headquarters in Cambridge, Mass., during the siege of Boston. The two men lived with Washington in Cambridge, with Reed serving as Washington's favorite military secretary and Moylan fulfilling the role during Reed's absence." Christian Science Monitor (Boston, MA).
- Touba, Mariam (November 5, 2014) Who Coined the Phrase 'United States of America'? You May Never Guess "Here, on January 2, 1776, seven months before the Declaration of Independence and a week before the publication of Paine's Common Sense, Stephen Moylan, an acting secretary to General George Washington, spells it out, 'I should like vastly to go with full and ample powers from the United States of America to Spain' to seek foreign assistance for the cause." New-York Historical Society Museum & Library
- Fay, John (July 15, 2016) The forgotten Irishman who named the 'United States of America' "According to the NY Historical Society, Stephen Moylan was the man responsible for the earliest documented use of the phrase 'United States of America'. But who was Stephen Moylan?" IrishCentral.com
- ""To the inhabitants of Virginia", by A PLANTER. Dixon and Hunter's. April 6, 1776, Williamsburg, Virginia. Letter is also included in Peter Force's American Archives". The Virginia Gazette. Vol. 5, no. 1287. Archived from the original on December 19, 2014.
- Safire 2003, p. 199.
- Mostert 2005, p. 18.
- Wilson, Kenneth G. (1993). The Columbia guide to standard American English. New York: Columbia University Press. pp. 27–28. ISBN 978-0-231-06989-2.
- Erlandson, Rick & Vellanoweth 2008, p. 19.
- Savage 2011, p. 55.
- Haviland, Walrath & Prins 2013, p. 219.
- Waters & Stafford 2007, pp. 1122–1126.
- Flannery 2015, pp. 173–185.
- Gelo 2018, pp. 79–80.
- Lockard 2010, p. 315.
- Martinez, Sage & Ono 2016, p. 4.
- Fagan 2016, p. 390.
- Stoltz, Julie Ann (2006). "Book Review of "The Continuance—An Algonquian Peoples Seminar: Selected Research Papers 2000", edited by Shirley Dunn, 2004, New York State Education Department, Albany, New York, 144 pages, $19.95 (paper)". Northeast Historical Archaeology. 35 (1): 201–202. doi:10.22191/neha/vol35/iss1/30. ISSN 0048-0738.
- Raster, Amanda; Hill, Christina Gish (May 24, 2016). "The dispute over wild rice: an investigation of treaty agreements and Ojibwe food sovereignty". Agriculture and Human Values. 34 (2): 267–281. doi:10.1007/s10460-016-9703-6. ISSN 0889-048X. S2CID 55940408.
- Dean R. Snow (1994). The Iroquois. Blackwell Publishers, Ltd. ISBN 978-1-55786-938-8. Retrieved July 16, 2010.
- Perdue & Green 2005, p. 40.
- Haines, Haines & Steckel 2000, p. 12.
- Thornton 1998, p. 34.
- "The New England Colonies and the Native Americans | National Geographic Society". History. Retrieved January 7, 2023.
- "Forgotten History: How The New England Colonists Embraced The Slave Trade". NPR. June 21, 2016. Retrieved January 7, 2023.
- Kiger, Patrick J. "How St. Augustine Became the First European Settlement in America". History. Retrieved January 7, 2023.
- Morison, Samuel Eliot (1971). The European Discovery of America: The Northern Voyages. New York: Oxford University Press. p. 490. ISBN 0-19-215941-0.
- Operé, Fernando (2008). Indian Captivity in Spanish America: Frontier Narratives. University of Virginia Press. p. 1. ISBN 978-0-8139-2587-5.
- "Not So Fast, Jamestown: St. Augustine Was Here First". NPR. February 28, 2015. Retrieved March 5, 2021.
- Petto, Christine Marie (2007). When France Was King of Cartography: The Patronage and Production of Maps in Early Modern France. Lexington Books. p. 125. ISBN 978-0-7391-6247-7.
- Seelye, James E. Jr.; Selby, Shawn (2018). Shaping North America: From Exploration to the American Revolution [3 volumes]. ABC-CLIO. p. 344. ISBN 978-1-4408-3669-5.
- Robert Neelly Bellah; Richard Madsen; William M. Sullivan; Ann Swidler; Steven M. Tipton (1985). Habits of the Heart: Individualism and Commitment in American Life. University of California Press. p. 220. ISBN 978-0-520-05388-5. OL 7708974M.
- Remini 2007, pp. 2–3
- Johnson 1997, pp. 26–30
- Cook, Noble (1998). Born to Die: Disease and New World Conquest, 1492–1650. Cambridge: Cambridge University Press. ISBN 978-0-521-62730-6.
- Treuer, David. "The new book 'The Other Slavery' will make you rethink American history". Los Angeles Times. Retrieved October 10, 2019.
- Stannard, 1993 p. xii
- "The Cambridge encyclopedia of human paleopathology Archived February 8, 2016, at the Wayback Machine". Arthur C. Aufderheide, Conrado Rodríguez-Martín, Odin Langsjoen (1998). Cambridge University Press. p. 205. ISBN 978-0-521-55203-5
- Bianchine, Russo, 1992 pp. 225–232
- Ripper, 2008 p. 6
- Ripper, 2008 p. 5
- Calloway, 1998, p. 55
- Joseph 2016, p. 590.
- Thomas, Hugh (1997). The Slave Trade: The Story of the Atlantic Slave Trade: 1440–1870. Simon and Schuster. pp. 516. ISBN 0-684-83565-7.
- Tadman, 2000, p. 1534
- Schneider, 2007, p. 484
- Lien, 1913, p. 522
- Davis, 1996, p. 7
- Quirk, 2011, p. 195
- Bilhartz, Terry D.; Elliott, Alan C. (2007). Currents in American History: A Brief History of the United States. M.E. Sharpe. ISBN 978-0-7656-1817-7.
- Wood, Gordon S. (1998). The Creation of the American Republic, 1776–1787. UNC Press Books. p. 263. ISBN 978-0-8078-4723-7.
- Walton, 2009, pp. 38–39
- Foner, Eric (1998). The Story of American Freedom (1st ed.). W.W. Norton. pp. 4–5. ISBN 978-0-393-04665-6.
story of American freedom.
- Walton, 2009, p. 35
- Otis, James (1763). The Rights of the British Colonies Asserted and Proved. ISBN 9780665526787.
- Reid, John Phillip (March 2003). Constitutional History of the American Revolution. ISBN 9780299139841.
- Recreating the American Republic – Charles A. Kromkowski. Retrieved on 2013-07-15.
- Humphrey, Carol Sue (2003). The Revolutionary Era: Primary Documents on Events from 1776 To 1800. Greenwood Publishing. pp. 8–10. ISBN 978-0-313-32083-5.
- "The First Continental Congress, 1774". Aoc.gov. Retrieved January 13, 2023.
- "Congress creates the Continental Association". HISTORY. November 9, 2009. Retrieved January 13, 2023.
- Fabian Young, Alfred; Nash, Gary B.; Raphael, Ray (2011). Revolutionary Founders: Rebels, Radicals, and Reformers in the Making of the Nation. Random House Digital. pp. 4–7. ISBN 978-0-307-27110-5.
- Miller, Hunter (ed.). "British-American Diplomacy: The Paris Peace Treaty of September 30, 1783". The Avalon Project at Yale Law School.
- Boyer, 2007, pp. 192–193
- Wait, Eugene M. (1999). America and the War of 1812. Nova Publishers. p. 78. ISBN 978-1-56072-644-9.
- Cogliano, Francis D. (2008). Thomas Jefferson: Reputation and Legacy. University of Virginia Press. p. 219. ISBN 978-0-8139-2733-6.
- Walton, 2009, p. 43
- Gordon, 2004, pp. 27,29
- Clark, Mary Ann (May 2012). Then We'll Sing a New Song: African Influences on America's Religious Landscape. Rowman & Littlefield. p. 47. ISBN 978-1-4422-0881-0.
- Heinemann, Ronald L., et al., Old Dominion, New Commonwealth: a history of Virginia 1607–2007, 2007 ISBN 978-0-8139-2609-4, p. 197
- Carlisle, Rodney P.; Golson, J. Geoffrey (2007). Manifest destiny and the expansion of America. Turning Points in History Series. Santa Barbara, Calif.: ABC-CLIO. p. 238. ISBN 978-1-85109-834-7. OCLC 659807062.
- Morrison, Michael A. (April 28, 1997). Slavery and the American West: The Eclipse of Manifest Destiny and the Coming of the Civil War. University of North Carolina Press. pp. 13–21. ISBN 978-0-8078-4796-1.
- "Louisiana Purchase" (PDF). National Park Service. Retrieved March 1, 2011.
- Klose, Nelson; Jones, Robert F. (1994). United States History to 1877. Barron's Educational Series. p. 150. ISBN 978-0-8120-1834-9.
- Kemp, Roger L. (2010). Documents of American Democracy: A Collection of Essential Works. McFarland. p. 180. ISBN 978-0-7864-4210-2. Retrieved October 25, 2015.
- Michno, Gregory (2003). Encyclopedia of Indian Wars: Western Battles and Skirmishes, 1850–1890. Mountain Press Publishing. ISBN 978-0-87842-468-9.
- Billington, Ray Allen; Ridge, Martin (2001). Westward Expansion: A History of the American Frontier. UNM Press. p. 22. ISBN 978-0-8263-1981-4.
- McIlwraith, Thomas F.; Muller, Edward K. (2001). North America: The Historical Geography of a Changing Continent. Rowman & Littlefield. p. 61. ISBN 978-0-7425-0019-8. Retrieved October 25, 2015.
- Wolf, Jessica. "Revealing the history of genocide against California's Native Americans". UCLA Newsroom. Retrieved July 8, 2018.
- Rawls, James J. (1999). A Golden State: Mining and Economic Development in Gold Rush California. University of California Press. p. 20. ISBN 978-0-520-21771-3.
- Paul Frymer, "Building an American Empire: The Era of Territorial and Political Expansion," (Princeton: Princeton University Press, 2017)
- Stuart Murray (2004). Atlas of American Military History. Infobase Publishing. p. 76. ISBN 978-1-4381-3025-5. Retrieved October 25, 2015.
Harold T. Lewis (2001). Christian Social Witness. Rowman & Littlefield. p. 53. ISBN 978-1-56101-188-9.
- O'Brien, Patrick Karl (2002). Atlas of World History (Concise ed.). New York, NY: Oxford University Press. p. 184. ISBN 978-0-19-521921-0.
- Vinovskis, Maris (1990). Toward A Social History of the American Civil War: Exploratory Essays. Cambridge; New York: Cambridge University Press. p. 4. ISBN 978-0-521-39559-5.
- Shearer Davis Bowman (1993). Masters and Lords: Mid-19th-Century U.S. Planters and Prussian Junkers. Oxford UP. p. 221. ISBN 978-0-19-536394-4.
- Jason E. Pierce (2016). Making the White Man's West: Whiteness and the Creation of the American West. University Press of Colorado. p. 256. ISBN 978-1-60732-396-9.
- Marie Price; Lisa Benton-Short (2008). Migrants to the Metropolis: The Rise of Immigrant Gateway Cities. Syracuse University Press. p. 51. ISBN 978-0-8156-3186-6.
- John Powell (2009). Encyclopedia of North American Immigration. Infobase Publishing. p. 74. ISBN 978-1-4381-1012-7. Retrieved October 25, 2015.
- Black, Jeremy (2011). Fighting for America: The Struggle for Mastery in North America, 1519–1871. Indiana University Press. p. 275. ISBN 978-0-253-35660-4.
- Winchester 2013, pp. 351, 385.
- "Purchase of Alaska, 1867". Office of the Historian. U.S. Department of State. Retrieved December 23, 2014.
- "The Spanish–American War, 1898". Office of the Historian. U.S. Department of State. Retrieved December 24, 2014.
- Ryden, George Herbert. The Foreign Policy of the United States in Relation to Samoa. New York: Octagon Books, 1975.
- "Virgin Islands History". Vinow.com. Retrieved January 5, 2018.
- Kirkland, Edward. Industry Comes of Age: Business, Labor, and Public Policy (1961 ed.). pp. 400–405.
- Zinn, 2005, pp. 321–357
- McDuffie, Jerome; Piggrem, Gary Wayne; Woodworth, Steven E. (2005). U.S. History Super Review. Piscataway, NJ: Research & Education Association. p. 418. ISBN 978-0-7386-0070-3.
- "The Great Migration (1910-1970)". May 20, 2021.
- Paige Meltzer, "The Pulse and Conscience of America" The General Federation and Women's Citizenship, 1945–1960," Frontiers: A Journal of Women Studies (2009), Vol. 30 Issue 3, pp. 52–76.
- James Timberlake, Prohibition and the Progressive Movement, 1900–1920 (Harvard UP, 1963)
- George B. Tindall, "Business Progressivism: Southern Politics in the Twenties," South Atlantic Quarterly 62 (Winter 1963): 92–106.
- Voris, Jacqueline Van (1996). Carrie Chapman Catt: A Public Life. Women and Peace Series. New York City: Feminist Press at CUNY. p. vii. ISBN 978-1-55861-139-9.
Carrie Chapmann Catt led an army of voteless women in 1919 to pressure Congress to pass the constitutional amendment giving them the right to vote and convinced state legislatures to ratify it in 1920. ... Catt was one of the best-known women in the United States in the first half of the twentieth century and was on all lists of famous American women.
- Winchester 2013, pp. 410–411.
- Axinn, June; Stern, Mark J. (2007). Social Welfare: A History of the American Response to Need (7th ed.). Boston: Allyn & Bacon. ISBN 978-0-205-52215-6.
- James Noble Gregory (1991). American Exodus: The Dust Bowl Migration and Okie Culture in California. Oxford University Press. ISBN 978-0-19-507136-8. Retrieved October 25, 2015.
"Mass Exodus From the Plains". American Experience. WGBH Educational Foundation. 2013. Retrieved October 5, 2014.
Fanslow, Robin A. (April 6, 1997). "The Migrant Experience". American Folklore Center. Library of Congress. Retrieved October 5, 2014.
Walter J. Stein (1973). California and the Dust Bowl Migration. Greenwood Press. ISBN 978-0-8371-6267-6. Retrieved October 25, 2015.
- The official WRA record from 1946 state it was 120,000 people. See War Relocation Authority (1946). The Evacuated People: A Quantitative Study. p. 8.. This number does not include people held in other camps such as those run by the DoJ or U.S. Army. Other sources may give numbers slightly more or less than 120,000.
- Yamasaki, Mitch. "Pearl Harbor and America's Entry into World War II: A Documentary History" (PDF). World War II Internment in Hawaii. Archived from the original (PDF) on December 13, 2014. Retrieved January 14, 2015.
- Stoler, Mark A. "George C. Marshall and the "Europe-First" Strategy, 1939–1951: A Study in Diplomatic as well as Military History" (PDF). Retrieved April 4, 2016.
- Kelly, Brian. "The Four Policemen and. Postwar Planning, 1943–1945: The Collision of Realist and. Idealist Perspectives". Retrieved June 21, 2014.
- Hoopes & Brinkley 1997, p. 100.
- Gaddis 1972, p. 25.
- Kennedy, Paul (1989). The Rise and Fall of the Great Powers. New York: Vintage. p. 358. ISBN 978-0-679-72019-5
- "The United States and the Founding of the United Nations, August 1941 – October 1945". U.S. Dept. of State, Bureau of Public Affairs, Office of the Historian. October 2005. Retrieved June 11, 2007.
- Woodward, C. Vann (1947). The Battle for Leyte Gulf. New York: Macmillan. ISBN 978-1-60239-194-9.
- "The Largest Naval Battles in Military History: A Closer Look at the Largest and Most Influential Naval Battles in World History". Military History. Norwich University. Archived from the original on December 8, 2015. Retrieved March 7, 2015.
- "Why did Japan surrender in World War II? | The Japan Times". The Japan Times. Retrieved February 8, 2017.
- Pacific War Research Society (2006). Japan's Longest Day. New York: Oxford University Press. ISBN 978-4-7700-2887-7.
- See Frankenfeld, Peter (2012). "A Marshall Plan for Greece? The European Union and the Financial Crisis in Greece. A Theoretical and Political Analysis in the Global World Against a Background of Regional Integration: Table 1. European Recovery Programme – Marshall Plan ($ million)". Prace i Materiały Instytutu Handlu Zagranicznego Uniwersytetu Gdańskiego (31/1): 69. ISSN 2300-6153.
- Wagg, Stephen; Andrews, David (2012). East Plays West: Sport and the Cold War. Routledge. p. 11. ISBN 978-1-134-24167-5.
- Blakemore, Erin (March 22, 2019). "What was the Cold War?". National Geographic. Retrieved August 28, 2020.
- Blakeley, 2009, p. 92
- Collins, Michael (1988). Liftoff: The Story of America's Adventure in Space. New York: Grove Press. ISBN 9780802110114.
- Chapman, Jessica M. (August 5, 2016). "Origins of the Vietnam War". Oxford Research Encyclopedia of American History. Oxford University Press. doi:10.1093/acrefore/9780199329175.013.353. ISBN 978-0-19-932917-5. Retrieved August 28, 2020.
- Winchester 2013, pp. 305–308.
- Blas, Elisheva. "The Dwight D. Eisenhower National System of Interstate and Defense Highways" (PDF). societyforhistoryeducation.org. Society for History Education. Retrieved January 19, 2015.
- Richard Lightner (2004). Hawaiian History: An Annotated Bibliography. Greenwood Publishing Group. p. 141. ISBN 978-0-313-28233-1.
- "The Civil Rights Movement". PBS.org. Retrieved January 5, 2019.
- "Social Security". ssa.gov. Retrieved October 25, 2015.
- Dallek, Robert (2004). Lyndon B. Johnson: Portrait of a President. Oxford University Press. p. 169. ISBN 978-0-19-515920-2.
- "Our Documents—Civil Rights Act (1964)". United States Department of Justice. Retrieved July 28, 2010.
- "Remarks at the Signing of the Immigration Bill, Liberty Island, New York". October 3, 1965. Archived from the original on May 16, 2016. Retrieved January 1, 2012.
- Levy, Daniel (January 19, 2018). "Behind the Protests Against the Vietnam War in 1968". Time Magazine. Retrieved May 5, 2021.
- Staff (August 25, 2022). "Playboy: American Magazine". Encyclopedia Britannica. Retrieved February 2, 2023.
...the so-called sexual revolution in the United States in the 1960s, marked by greatly more permissive attitudes toward sexual interest and activity than had been prevalent in earlier generations.
- Julia Goicichea (August 16, 2017). "Why New York City Is a Major Destination for LGBT Travelers". The Culture Trip. Retrieved July 15, 2022.
- "Brief History of the Gay and Lesbian Rights Movement in the U.S". University of Kentucky. Retrieved July 15, 2022.; Nell Frizzell (June 28, 2013). "Feature: How the Stonewall riots started the LGBT rights movement". Pink News UK. Retrieved July 15, 2022.; "Stonewall riots". Encyclopædia Britannica. Retrieved July 15, 2022.
- "Women in the Labor Force: A Databook" (PDF). U.S. Bureau of Labor Statistics. 2013. p. 11. Retrieved March 21, 2014.
- Ervin, Sam, et al., Final Report of the Watergate Committee].
- Gerstle 2022, pp. 106–108, 121–128.
- Soss, 2010, p. 277
- Fraser, 1989
- Federal Debt Held by the Public (Report). Federal Reserve Bank of St. Louis. May 31, 2018. Retrieved June 12, 2018.
- "Reagan Policies Gave Green Light to Red Ink". The Washington Post. June 9, 2004. Retrieved May 25, 2007.
- Howell, Buddy Wayne (2006). The Rhetoric of Presidential Summit Diplomacy: Ronald Reagan and the U.S.-Soviet Summits, 1985–1988. Texas A&M University. p. 352. ISBN 978-0-549-41658-6.
- Kissinger, Henry (2011). Diplomacy. Simon & Schuster. pp. 781–784. ISBN 978-1-4391-2631-8. Retrieved October 25, 2015.
Mann, James (2009). The Rebellion of Ronald Reagan: A History of the End of the Cold War. Penguin. p. 432. ISBN 978-1-4406-8639-9.
- Hayes, 2009
- Charles Krauthammer, "The Unipolar Moment", Foreign Affairs, 70/1, (Winter 1990/1), 23–33.
- Judt, Tony; Lacorne, Denis (2005). With Us Or Against Us: Studies in Global Anti-Americanism. Palgrave Macmillan. p. 61. ISBN 978-1-4039-8085-4.
Richard J. Samuels (2005). Encyclopedia of United States National Security. Sage Publications. p. 666. ISBN 978-1-4522-6535-3.
Paul R. Pillar (2001). Terrorism and U.S. Foreign Policy. Brookings Institution Press. p. 57. ISBN 978-0-8157-0004-3.
Gabe T. Wang (2006). China and the Taiwan Issue: Impending War at Taiwan Strait. University Press of America. p. 179. ISBN 978-0-7618-3434-2.
Understanding the "Victory Disease", From the Little Bighorn to Mogadishu and Beyond. Diane Publishing. 2004. p. 1. ISBN 978-1-4289-1052-2.
Akis Kalaitzidis; Gregory W. Streich (2011). U.S. Foreign Policy: A Documentary and Reference Guide. ABC-CLIO. p. 313. ISBN 978-0-313-38375-5.
Cohen, 2004: History and the Hyperpower
- Halliday, Fred (April 1991). "The Gulf War and Its Aftermath: First Reflections". International Affairs. Oxford University Press. 67 (2): 223–234. doi:10.2307/2620827. JSTOR 2620827. S2CID 154565052.
- "North American Free Trade Agreement (NAFTA) | United States Trade Representative". www.ustr.gov. Archived from the original on March 17, 2013. Retrieved January 11, 2015.
Thakur; Manab Thakur Gene E Burton B N Srivastava (1997). International Management: Concepts and Cases. Tata McGraw-Hill Education. pp. 334–335. ISBN 978-0-07-463395-3. Retrieved October 25, 2015.
Akis Kalaitzidis; Gregory W. Streich (2011). U.S. Foreign Policy: A Documentary and Reference Guide. ABC-CLIO. p. 201. ISBN 978-0-313-38376-2.
- Dale, Reginald (February 18, 2000). "Did Clinton Do It, or Was He Lucky?". The New York Times. Retrieved March 6, 2013.
Mankiw, N. Gregory (2008). Macroeconomics. Cengage Learning. p. 559. ISBN 978-0-324-58999-3. Retrieved October 25, 2015.
- Flashback 9/11: As It Happened. Fox News. September 9, 2011. Retrieved March 6, 2013.
"America remembers Sept. 11 attacks 11 years later". CBS News. Associated Press. September 11, 2012. Archived from the original on October 17, 2013. Retrieved March 6, 2013.
"Day of Terror Video Archive". CNN. 2005. Retrieved March 6, 2013.
- Walsh, Kenneth T. (December 9, 2008). "The 'War on Terror' Is Critical to President George W. Bush's Legacy". U.S. News & World Report. Retrieved March 6, 2013.
Atkins, Stephen E. (2011). The 9/11 Encyclopedia: Second Edition. ABC-CLIO. p. 872. ISBN 978-1-59884-921-9. Retrieved October 25, 2015.
- Wong, Edward (February 15, 2008). "Overview: The Iraq War". The New York Times. Retrieved March 7, 2013.
Johnson, James Turner (2005). The War to Oust Saddam Hussein: Just War and the New Face of Conflict. Rowman & Littlefield. p. 159. ISBN 978-0-7425-4956-2. Retrieved October 25, 2015.
Durando, Jessica; Green, Shannon Rae (December 21, 2011). "Timeline: Key moments in the Iraq War". USA Today. Associated Press. Archived from the original on September 4, 2020. Retrieved March 7, 2013.
- Wallison, Peter (2015). Hidden in Plain Sight: What Really Caused the World's Worst Financial Crisis and Why It Could Happen Again. Encounter Books. ISBN 978-978-59407-7-0.
- Financial Crisis Inquiry Commission (2011). Financial Crisis Inquiry Report (PDF). ISBN 978-1-60796-348-6.
- Taylor, John B. (January 2009). "The Financial Crisis and the Policy Responses: An Empirical Analysis of What Went Wrong" (PDF). Hoover Institution Economics Paper Series. Retrieved January 21, 2017.
- Hilsenrath, Jon; Ng, Serena; Paletta, Damian (September 18, 2008). "Worst Crisis Since '30s, With No End Yet in Sight". The Wall Street Journal.
- "Barack Obama: Face Of New Multiracial Movement?". NPR. November 12, 2008.
- Washington, Jesse; Rugaber, Chris (July 10, 2011). "African-American Economic Gains Reversed By Great Recession". Associated Press. Archived from the original on June 16, 2013.
- "In Defense of Obama". Rolling Stone. October 8, 2014. Archived from the original on November 19, 2016. Retrieved November 19, 2016.
- "CEA 2017 Economic Report of the President-Chapter One-Eight Years of Recovery and Reinvestment" (PDF). Whitehouse.gov. Retrieved March 12, 2017.
- "Everything is Awesome". Politico.com. Retrieved December 30, 2016.
- Jackson, Brooks (January 20, 2017). "What President Trump Inherits" – via Factcheck.org.
- Jackson, Brooks (September 29, 2017). "Obama's Final Numbers" – via Factcheck.org.
- Uberoi, Namrata; Finegold, Kenneth; Gee, Emily (March 2, 2016). "Health Insurance Coverage and the Affordable Care Act, 2010–2016" (PDF). Assistant Secretary for Planning and Evaluation. U.S. Department of Health and Human Services. Archived from the original on December 5, 2011. Retrieved December 7, 2016.
- Smith, Harrison (November 9, 2016). "Donald Trump is elected president of the United States". The Washington Post. Retrieved October 27, 2020.
- Kochhar, Rakesh. "Unemployment rose higher in three months of COVID-19 than it did in two years of the Great Recession". Pew Research Center. Retrieved October 1, 2022.
- Taylor, Derrick Bryson (June 2, 2020). "George Floyd Protests: A Timeline". The New York Times. Archived from the original on June 2, 2020. Retrieved June 2, 2020.
- Javanbakht M.D., Arash (March 29, 2021). "How Mass Shootings Leave Emotional Scars on Society". www.psychologytoday.com. Psychology Today. Retrieved October 3, 2022.
- Peñaloza, Marisa (January 6, 2021). "Trump Supporters Storm U.S. Capitol, Clash with Police". NPR. NPR. Retrieved January 16, 2021.
- "Protests erupt in D.C., around the country as Roe v. Wade falls". Washington Post. ISSN 0190-8286. Retrieved September 28, 2022.
- "The Senate has approved roughly $40 billion in aid to Ukraine". NPR.org. Retrieved September 28, 2022.
- "Field Listing: Area". The World Factbook. cia.gov. Archived from the original on July 7, 2020. Retrieved April 21, 2020.
- "State Area Measurements and Internal Point Coordinates—Geography—U.S. Census Bureau". State Area Measurements and Internal Point Coordinates. U.S. Department of Commerce. Retrieved September 11, 2017.
- "2010 Census Area" (PDF). census.gov. U.S. Census Bureau. p. 41. Retrieved January 18, 2015.
- "Area". The World Factbook. Central Intelligence Agency. Archived from the original on January 31, 2014. Retrieved January 15, 2015.
- "United States". The World Factbook. Central Intelligence Agency. January 3, 2018. Retrieved January 8, 2018.
- "Geographic Regions of Georgia". Georgia Info. Digital Library of Georgia. Retrieved December 24, 2014.
- Lew, Alan. "PHYSICAL GEOGRAPHY OF THE US". GSP 220—Geography of the United States. North Arizona University. Archived from the original on April 9, 2016. Retrieved December 24, 2014.
- Harms, Nicole. "Facts About the Rocky Mountain Range". Travel Tips. USA Today. Retrieved December 24, 2014.
- Tinkham, Ernest R. (March 1944). "Biological, Taxonomic and Faunistic Studies on the Shield-Back Katydids of the North American Deserts". The American Midland Naturalist. The University of Notre Dame. 31 (2): 257–328. doi:10.2307/2421073. JSTOR 2421073.
- "Mount Whitney, California". Peakbagger. Retrieved December 24, 2014.
- "Find Distance and Azimuths Between 2 Sets of Coordinates (Badwater 36-15-01-N, 116-49-33-W and Mount Whitney 36-34-43-N, 118-17-31-W)". Federal Communications Commission. Retrieved December 24, 2014.
- Poppick, Laura (August 28, 2013). "US Tallest Mountain's Surprising Location Explained". LiveScience. Retrieved May 2, 2015.
- O'Hanlon, Larry (March 14, 2005). "America's Explosive Park". Discovery Channel. Archived from the original on March 14, 2005. Retrieved April 5, 2016.
- Boyden, Jennifer. "Climate Regions of the United States". Travel Tips. USA Today. Retrieved December 24, 2014.
- "World Map of Köppen–Geiger Climate Classification" (PDF). Archived from the original (PDF) on January 26, 2022. Retrieved August 19, 2015.
- Perkins, Sid (May 11, 2002). "Tornado Alley, USA". Science News. Archived from the original on July 1, 2007. Retrieved September 20, 2006.
- Rice, Doyle. "USA has the world's most extreme weather". USA Today. Retrieved May 17, 2020.
- US EPA, OAR (June 27, 2016). "Climate Change Indicators: Weather and Climate". www.epa.gov. Retrieved June 19, 2022.
- Len McDougall (2004). The Encyclopedia of Tracks and Scats: A Comprehensive Guide to the Trackable Animals of the United States and Canada. Lyons Press. p. 325. ISBN 978-1-59228-070-4.
- Morin, Nancy. "Vascular Plants of the United States" (PDF). Plants. National Biological Service. Archived from the original (PDF) on July 24, 2013. Retrieved October 27, 2008.
- Osborn, Liz. "Number of Native Species in United States". Current Results Nexus. Retrieved January 15, 2015.
- "Numbers of Insects (Species and Individuals)". Smithsonian Institution. Retrieved January 20, 2009.
- Park, National. "National Park FAQ". nps. Retrieved May 8, 2015.
- Lipton, Eric; Krauss, Clifford (August 23, 2012). "Giving Reins to the States Over Drilling". The New York Times. Retrieved January 18, 2015.
- Vincent, Carol H.; Hanson, Laura A.; Argueta, Carla N. (March 3, 2017). Federal Land Ownership: Overview and Data (Report). Congressional Research Service. p. 2. Retrieved June 18, 2020.
- Gorte, Ross W.; Vincent, Carol Hardy.; Hanson, Laura A.; Marc R., Rosenblum. "Federal Land Ownership: Overview and Data" (PDF). fas.org. Congressional Research Service. Retrieved January 18, 2015.
- "Chapter 6: Federal Programs to Promote Resource Use, Extraction, and Development". doi.gov. U.S. Department of the Interior. Archived from the original on March 18, 2015. Retrieved January 19, 2015.
- The National Atlas of the United States of America (January 14, 2013). "Forest Resources of the United States". Nationalatlas.gov. Archived from the original on May 7, 2009. Retrieved January 13, 2014.
- "Land Use Changes Involving Forestry in the United States: 1952 to 1997, With Projections to 2050" (PDF). 2003. Retrieved January 13, 2014.
- Daynes & Sussman, 2010, pp. 3, 72, 74–76, 78
- Hays, Samuel P. (2000). A History of Environmental Politics since 1945.
- Collin, Robert W. (2006). The Environmental Protection Agency: Cleaning Up America's Act. Greenwood Publishing Group. p. 1. ISBN 978-0-313-33341-5. Retrieved October 25, 2015.
- Turner, James Morton (2012). The Promise of Wilderness
- Endangered species Fish and Wildlife Service. General Accounting Office, Diane Publishing. 2003. p. 1. ISBN 978-1-4289-3997-4. Retrieved October 25, 2015.
- "What Is the Greenest Country in the World?". Atlas & Boots. Environmental Performance Index. June 6, 2020. Retrieved November 18, 2020.
- "United States of America". Global Climate Action – NAZCA. United Nations. Retrieved November 18, 2020.
- Nugent, Ciara (November 4, 2020). "The U.S. Just Officially Left the Paris Agreement. Can it Be a Leader in the Climate Fight Again?". Times. Retrieved November 18, 2020.
- "Biden announces return to global climate accord, new curbs on U.S. oil industry". Money News. Reuters. January 20, 2021. Retrieved February 9, 2021.
- "Common Core Document of the United States of America". U.S. Department of State. December 30, 2011. Retrieved July 10, 2015.
- The New York Times 2007, p. 670.
- Onuf 2010, p. xvii.
- Scheb, John M.; Scheb, John M. II (2002). An Introduction to the American Legal System. Florence, KY: Delmar, p. 6. ISBN 978-0-7668-2759-2.
- Feldstein, Fabozzi, 2011, p. 9
- Schultz, 2009, pp. 164, 453, 503
- Etheridge, Eric; Deleith, Asger (August 19, 2009). "A Republic or a Democracy?". The New York Times blogs. Retrieved November 7, 2010.
The US system seems essentially a two-party system. ...
- David Mosler; Robert Catley (1998). America and Americans in Australia. Greenwood Publishing Group. p. 83. ISBN 978-0-275-96252-4. Retrieved April 11, 2016.
- Grigsby, Ellen (2008). Analyzing Politics: An Introduction to Political Science. Cengage Learning. pp. 106–107. ISBN 978-0-495-50112-1.
- "Corruption Perceptions Index 2019" (PDF). transparency.org. Transparency International. p. 12 & 13. Archived from the original (PDF) on February 18, 2020. Retrieved February 7, 2020.
- Francis, Ellen (February 10, 2022). "Global freedoms have hit a 'dismal' record low, with pandemic restrictions making things worse, report says". The Washington Post. ISSN 0190-8286. Retrieved February 18, 2022.
- Killian, Johnny H. "Constitution of the United States". The Office of the Secretary of the Senate. Retrieved February 11, 2012.
- "The Legislative Branch". United States Diplomatic Mission to Germany. Retrieved August 20, 2012.
- "The Process for impeachment". ThinkQuest. Archived from the original on April 8, 2013. Retrieved August 20, 2012.
- "The Executive Branch". The White House. Retrieved February 11, 2017.
- Kermit L. Hall; Kevin T. McGuire (2005). Institutions of American Democracy: The Judicial Branch. Oxford University Press. ISBN 978-0-19-988374-5.
U.S. Citizenship and Immigration Services (2013). Learn about the United States: Quick Civics Lessons for the Naturalization Test. Government Printing Office. p. 4. ISBN 978-0-16-091708-0.
Bryon Giddens-White (2005). The Supreme Court and the Judicial Branch. Heinemann Library. ISBN 978-1-4034-6608-2.
Charles L. Zelden (2007). The Judicial Branch of Federal Government: People, Process, and Politics. ABC-CLIO. ISBN 978-1-85109-702-9. Retrieved October 25, 2015.
"Federal Courts". United States Courts. Retrieved October 19, 2014.
- Locker, Melissa (March 9, 2015). "Watch John Oliver Cast His Ballot for Voting Rights for U.S. Territories". Time. Retrieved November 11, 2019.
- Shell, Donald; Baldwin, Nicholas (2013). Second Chambers. Taylor & Francis. p. 43. ISBN 9781136337000.
The United States Senate is frequently characterised as the most powerful upper house in the world.
- Avaliktos, Neal (2004). The Election Process Revisited. Nova Publishers. p. 111. ISBN 978-1-59454-054-7.
- Cossack, Roger (July 13, 2000). "Beyond politics: Why Supreme Court justices are appointed for life". CNN. Archived from the original on July 12, 2012.
- 8 U.S.C. § 1101(a)(36) and 8 U.S.C. § 1101(a)(38) U.S. Federal Code, Immigration and Nationality Act. 8 U.S.C. § 1101a
- "Electoral College Fast Facts | U.S. House of Representatives: History, Art & Archives". history.house.gov. Retrieved August 21, 2015.
- "American Samoa and the Citizenship Clause: A Study in Insular Cases Revisionism". harvardlawreview.org. Retrieved January 5, 2018.
- Alvarez, Priscilla (December 12, 2019). "Federal judge rules American Samoans are US citizens by birth". CNN. Retrieved October 6, 2020.
- Romboy, Dennis (December 13, 2019). "Judge puts citizenship ruling for American Samoans on hold". KSL.com. Retrieved October 6, 2020.
- Keating, Joshua (June 5, 2015). "How Come American Samoans Still Don't Have U.S. Citizenship at Birth?" – via Slate.
- "Frequently Asked Questions". U.S. Department of the Interior Indian Affairs. Retrieved January 16, 2016.
- "Tribal Geography in Relation to State Boundaries".
- "Global Diplomacy Index – Country Rank". Lowy Institute. Retrieved July 15, 2022.
- "Current Members". United Nations Security Council. Retrieved July 15, 2022.
- "United Nations Headquarters Agreement". The American Journal of International Law. Cambridge University Press. 42 (2): 445–447. April 1948. doi:10.2307/2193692. JSTOR 2193692. S2CID 246008694.
- "Where is the G7 Headed?". Council on Foreign Relations. New York City. June 28, 2022.
- "The United States and G20: Building a More Peaceful, Stable, and Prosperous World Together". United States Department of State. July 6, 2022. Retrieved July 15, 2022.
- "Our global reach". OECD. Retrieved July 15, 2022.
- Fialho, Livia Pontes; Wallin, Matthew (August 1, 2013). Reaching for an Audience: U.S. Public Diplomacy Towards Iran (Report). American Security Project. JSTOR resrep06070.
- Oliver, Alex; Graham, Euan (December 19, 2017). "Which are the countries still talking to North Korea?". BBC News. London. Retrieved July 15, 2022.
The United States has never established diplomatic relations with North Korea.
- Ferraro, Matthew F. (December 22, 2014). "The Case for Stronger Bhutanese-American Ties". The Diplomat. Retrieved July 15, 2022.
While Bhutan joined the United Nations in 1971, it does not have diplomatic relations with any of the permanent members of the UN Security Council, including the United States and China.
- Ruwitch, John (September 22, 2020). "Formal Ties With U.S.? Not For Now, Says Taiwan Foreign Minister". NPR. Retrieved July 15, 2022.
- Dumbrell, John; Schäfer, Axel (2009). America's 'Special Relationships': Foreign and Domestic Aspects of the Politics of Alliance. p. 45. ISBN 978-0-203-87270-3. Retrieved October 25, 2015.
- Ek, Carl & Ian F. Fergusson (September 3, 2010). "Canada–U.S. Relations" (PDF). Congressional Research Service. Retrieved August 28, 2011.
- Vaughn, Bruce (August 8, 2008). Australia: Background and U.S. Relations. Congressional Research Service. OCLC 70208969.
- Vaughn, Bruce (May 27, 2011). "New Zealand: Background and Bilateral Relations with the United States" (PDF). Congressional Research Service. Retrieved August 28, 2011.
- Lum, Thomas (January 3, 2011). "The Republic of the Philippines and U.S. Interests" (PDF). Congressional Research Service. Retrieved August 3, 2011.
- Chanlett-Avery, Emma; et al. (June 8, 2011). "Japan-U.S. Relations: Issues for Congress" (PDF). Congressional Research Service. Retrieved August 28, 2011.
- Mark E. Manyin; Emma Chanlett-Avery; Mary Beth Nikitin (July 8, 2011). "U.S.–South Korea Relations: Issues for Congress" (PDF). Congressional Research Service. Retrieved August 28, 2011.
- Zanotti, Jim (July 31, 2014). "Israel: Background and U.S. Relations" (PDF). Congressional Research Service. Retrieved September 12, 2014.
- "U.S. Relations With Poland".
- Kimer, James (September 26, 2019). "The Untapped Potential of the US-Colombia Partnership". Atlantic Council. Retrieved May 30, 2020.
- "U.S. Relations With Colombia". United States Department of State. Retrieved May 30, 2020.
- Charles L. Zelden (2007). The Judicial Branch of Federal Government: People, Process, and Politics. ABC-CLIO. p. 217. ISBN 978-1-85109-702-9. Retrieved October 25, 2015.
Loren Yager; Emil Friberg; Leslie Holen (2003). Foreign Relations: Migration from Micronesian Nations Has Had Significant Impact on Guam, Hawaii, and the Commonwealth of the Northern Mariana Islands. Diane Publishing. p. 7. ISBN 978-0-7567-3394-0.
- Macias, Amanda. "Here's a look at the $5.6 billion in firepower the U.S. has committed to Ukraine in its fight against Russia". CNBC. Retrieved September 28, 2022.
- Rumer, Eugene; Sokolsky, Richard (June 20, 2019). "Thirty Years of U.S. Policy Toward Russia: Can the Vicious Circle Be Broken?". Carnegie Endowment for International Peace. Washington, D.C. Retrieved July 14, 2022.
- Meidan, Michal (July 1, 2019). US-China: The Great Decoupling (Report). Oxford Institute for Energy Studies. JSTOR resrep33982.
- "US will continue to strengthen 'unofficial ties' with Taiwan, says Harris". South China Morning Post. September 28, 2022. Retrieved September 28, 2022.
- Lindsay, James M. (August 4, 2021). "Happy 231st Birthday to the United States Coast Guard!". New York City: Council on Foreign Relations. Retrieved July 16, 2022.
During peacetime it is part of the Department of Homeland Security. During wartime, or when the president or Congress so direct, it becomes part of the Department of Defense and is included in the Department of the Navy.
- "World military expenditure grows to $1.8 trillion in 2018". sipri.org. Stockholm International Peace Research Institute. April 19, 2019. Archived from the original on September 22, 2020. Retrieved September 23, 2020.
- Reichmann, Kelsey (June 16, 2019). "Here's how many nuclear warheads exist, and which countries own them". defensenews.com. Sightline Media Group. Archived from the original on September 23, 2020. Retrieved September 23, 2020.
- The Military Balance 2019. London: International Institute for Strategic Studies. 2019. p. 47. ISBN 978-1-85743-988-5. Archived from the original on September 22, 2020. Retrieved September 23, 2020.
- "READ: James Mattis' resignation letter". CNN. December 21, 2018. Archived from the original on December 4, 2019. Retrieved January 8, 2020.
- "What does Selective Service provide for America?". Selective Service System. Archived from the original on September 15, 2012. Retrieved February 11, 2012.
- IISS 2020, pp. 46
- "Noble Eagle Without End". Retrieved February 1, 2005.
- "The Ups and Downs of Close Air Support". Retrieved December 1, 2019.
- "Building the Space Range of the Future". Retrieved May 1, 2020.
- "Global Positioning System". www.schriever.spaceforce.mil.
- "Space surveillance technologies a top need for U.S. military". November 22, 2020. Retrieved November 22, 2020.
- Harris, Johnny (May 18, 2015). "Why does the US have 800 military bases around the world?". Vox. Archived from the original on September 24, 2020. Retrieved September 23, 2020.
- "Active Duty Military Personnel Strengths by Regional Area and by Country (309A)" (PDF). Department of Defense. March 31, 2010. Archived from the original (PDF) on July 24, 2013. Retrieved October 7, 2010.
- Banks, Duren; Hendrix, Joshua; Hickman, Mathhew (October 4, 2016). "National Sources of Law Enforcement Employment Data" (PDF). U.S. Department of Justice: 1.
- "U.S. Federal Law Enforcement Agencies, Who Governs & What They Do". Chiff.com. Archived from the original on February 10, 2014. Retrieved November 10, 2021.
- Manweller, Mathew (2006). "Chapter 2, The Roles, Functions, and Powers of State Courts". In Hogan, Sean O. (ed.). The Judicial Branch of State Government: People, Process, and Politics. Santa Barbara, California: ABC-Clio. pp. 37–96. ISBN 978-1-851-09751-7. Retrieved October 5, 2020.
- "Introduction To The Federal Court System". United States Attorney. Washington, D.C.: United States Department of Justice. November 7, 2014. Retrieved July 14, 2022.
- "Intentional homicides (per 100,000 people) - United States". World Bank. Retrieved July 14, 2022.
- Grinshteyn, Erin; Hemenway, David (March 2016). "Violent Death Rates: The US Compared with Other High-income OECD Countries, 2010". The American Journal of Medicine. 129 (3): 226–273. doi:10.1016/j.amjmed.2015.10.025. PMID 26551975. Retrieved June 18, 2017.
- Haymes et al., 2014, p. 389
- "US Department of Justice, Oct. 22, 2020" (PDF).
- Sawyer, Wendy; Wagner, Peter (March 24, 2020). Mass Incarceration: The Whole Pie 2020 (Report). Prison Policy Initiative. Retrieved January 23, 2021.
- Schrantz, Dennis; DeBor, Stephen; Mauer, Marc (September 5, 2018). "Decarceration Strategies: How 5 States Achieved Substantial Prison Population Reductions". Washington, D.C.: The Sentencing Project. Retrieved July 16, 2022.
- Mikaila Mariel Lemonik Arthur (2020). Law and Justice around the World: A Comparative Approach. Univ of California Press. pp. 179–180. ISBN 978-0-520-30001-9.
- "Death Penalty States ". Death Penalty Info. Retrieved September 8, 2022.
- Connor, Tracy; Chuck, Elizabeth (May 28, 2015). "Nebraska's Death Penalty Repealed With Veto Override". NBC News. Retrieved June 11, 2015.
- Simpson, Ian (May 2, 2013). "Maryland becomes latest U.S. state to abolish death penalty". Reuters. Retrieved April 6, 2016.
- "State by State". Death Penalty Information Center. Retrieved October 6, 2020.
- "Searchable Execution Database". Death Penalty Information Center. Retrieved October 10, 2012.
- "Death Sentences and Executions 2019". Amnesty International USA. 2019. Retrieved May 30, 2020.
- DPIC adds Eleven cases to the Innocence List bringing national death-row exonerations to 185, Death Penalty Information Center, Robert Durham, February 18, 2021. Retrieved November 9, 2021.
- "The Implementation of Monetary Policy – The Federal Reserve in the International Sphere" (PDF). Retrieved August 24, 2010.
- Kat Tretina and Benjamin Curry (April 9, 2021). "NYSE: What Is The New York Stock Exchange". Forbes. Retrieved July 24, 2022.
- "Report for Selected Countries and Subjects". www.imf.org.
- Hagopian, Kip; Ohanian, Lee (August 1, 2012). "The Mismeasure of Inequality". Policy Review (174). Archived from the original on December 3, 2013. Retrieved January 23, 2020.
- "United Nations Statistics Division—National Accounts". unstats.un.org. Retrieved June 1, 2018.
- Fordham, Benjamin (October 2017). "Protectionist Empire: Trade, Tariffs, and United States Foreign Policy, 1890–1914". Studies in American Political Development. 31 (2): 170–192. doi:10.1017/s0898588x17000116. ISSN 0898-588X. S2CID 148917255.
- "United States reference resource". The World Factbook Central Intelligence Agency. Retrieved May 31, 2019.
- Wright, Gavin, and Jesse Czelusta, "Resource-Based Growth Past and Present", in Natural Resources: Neither Curse Nor Destiny, ed. Daniel Lederman and William Maloney (World Bank, 2007), p. 185. ISBN 0821365452.
- Anthony, Craig (September 12, 2016). "10 Countries With The Most Natural Resources". Investopedia.
- "Income". Better Life Index. OECD. Retrieved September 28, 2019.
In the United States, the average household net adjusted disposable income per capita is USD 45 284 a year, much higher than the OECD average of USD 33 604 and the highest figure in the OECD.
- "Household Income". Society at a Glance 2014: OECD Social Indicators. Society at a Glance. OECD Publishing. March 18, 2014. doi:10.1787/soc_glance-2014-en. ISBN 9789264200722. Retrieved May 29, 2014.
- "OECD Better Life Index". OECD. Retrieved November 25, 2012.
- Zaw Thiha Tun (July 29, 2015). "How Petrodollars Affect The U.S. Dollar". Retrieved October 14, 2016.
- Benjamin J. Cohen, The Future of Money, Princeton University Press, 2006, ISBN 0691116660; cf. "the dollar is the de facto currency in Cambodia", Charles Agar, Frommer's Vietnam, 2006, ISBN 0471798169, p. 17
- "US GDP Growth Rate by Year". multpl.com. US Bureau of Economic Analysis. March 31, 2014. Retrieved June 18, 2014.
- "Monthly Reports - World Federation of Exchanges". WFE.
- Table A – Market Capitalization of the World's Top Stock Exchanges (As at end of June 2012). Securities and Exchange Commission (China).
- "Top Trading Partners". U.S. Census Bureau. December 2016. Retrieved July 8, 2017.
- "World Trade Statistical Review 2019" (PDF). World Trade Organization. p. 100. Retrieved May 31, 2019.
- "United States free trade agreements". Office of the United States Trade Representative. Retrieved May 31, 2019.
- "Rankings: Global Competitiveness Report 2013–2014" (PDF). World Economic Forum. Retrieved June 1, 2014.
- "Global 500 2016". Fortune. Archived from the original on September 21, 2018. Retrieved January 30, 2023. Number of companies data taken from the "Country" filter.
- "USA Economy in Brief". U.S. Dept. of State, International Information Programs. Archived from the original on March 12, 2008.
- Isabelle Joumard; Mauro Pisu; Debbie Bloch (2012). "Tackling income inequality The role of taxes and transfers" (PDF). OECD. Retrieved May 21, 2015.
- "CIA World Factbook "Distribution of Family Income"". Archived from the original on June 4, 2011. Retrieved June 17, 2018.
- Gray, Sarah (June 4, 2018). "Trump Policies Highlighted in Scathing U.N. Report On U.S. Poverty". Fortune. Retrieved September 13, 2018.
"The United States has the highest rate of income inequality among Western countries", the report states.
- ""Contempt for the poor in US drives cruel policies," says UN expert". OHCHR. June 4, 2018. Retrieved June 5, 2018.
- Rappeport, Alan; Tankersley, Jim (October 4, 2022). "U.S. National Debt Tops $31 Trillion for First Time". The New York Times. ISSN 0362-4331. Retrieved January 1, 2023.
- "Trends in Family Wealth, 1989 to 2013". Congressional Budget Office. August 18, 2016. Retrieved November 29, 2016.
- "Income Distribution: Median equivalised disposable income". OECD. Retrieved January 21, 2023.
- Shorrocks, Anthony; Davies, James; Lluberas, Rodrigo (2021). Global wealth databook 2021 (PDF). Credit Suisse Research Institute.
- Jackson, Sarah. "These 20 countries and territories are home to most of the world's 2,755 billionaires". Business Insider. Retrieved July 15, 2022.
- Exley, Robert Jr. (December 22, 2021). "Nearly 22 million Americans are millionaires. Here's how they got wealthy". CNBC. Retrieved July 16, 2022.
- Piketty, Thomas (2014). Capital in the Twenty-First Century. Belknap Press. p. 257. ISBN 978-0-674-43000-6
- "Income inequality in America is the highest it's been since Census Bureau started tracking it, data shows". The Washington Post. Retrieved July 27, 2020.
- Long, Heather (September 12, 2017). "U.S. middle-class incomes reached highest-ever level in 2016, Census Bureau says". The Washington Post. Retrieved November 11, 2019.
- Smeeding, T.M. (2005). "Public Policy: Economic Inequality and Poverty: The United States in Comparative Perspective". Social Science Quarterly. 86: 955–983. doi:10.1111/j.0038-4941.2005.00331.x. S2CID 154642286.
- Min, Sarah (May 24, 2019). "1 in 4 workers in U.S. don't get any paid vacation time or holidays". CBS News. Retrieved July 15, 2022.
The United States is the only advanced economy that does not federally mandate any paid vacation days or holidays.
- Bernard, Tara Siegel (February 22, 2013). "In Paid Family Leave, U.S. Trails Most of the Globe". The New York Times. Retrieved August 27, 2013.
- Van Dam, Andrew (July 4, 2018). "Is it great to be a worker in the U.S.? Not compared with the rest of the developed world". The Washington Post. Retrieved July 12, 2018.
- Anne McDonald Culp, ed. (June 25, 2013). Child and Family Advocacy: Bridging the Gaps Between Research, Practice, and Policy. Springer Science & Business Media. pp. 77–. ISBN 978-1-4614-7456-2. OCLC 1026456872.
- Fowler, P. J.; Hovmand, P. S.; Marcal, K. E.; Das, S. (2019). "Solving Homelessness from a Complex Systems Perspective: Insights for Prevention Responses". Annual Review of Public Health. 40: 465–486. doi:10.1146/annurev-publhealth-040617-013553. PMC 6445694. PMID 30601718.
- "Household Food Security in the United States in 2011" (PDF). USDA. September 2012. Archived from the original (PDF) on October 7, 2012. Retrieved April 8, 2013.
- Hounshell, David A. (1984), From the American System to Mass Production, 1800–1932: The Development of Manufacturing Technology in the United States, Baltimore, Maryland: Johns Hopkins University Press, ISBN 978-0-8018-2975-8, LCCN 83016269, OCLC 1104810110
- "Research and Development (R&D) Expenditures by Source and Objective: 1970 to 2004". U.S. Census Bureau. Archived from the original on February 10, 2012. Retrieved June 19, 2007.
- "SJR - International Science Ranking". www.scimagojr.com. Retrieved July 3, 2022.
- Szmigiera, M. (November 26, 2021). "Ranking of the 20 countries with most patent grants". Statista. Retrieved July 3, 2022.
- Hines, R. Lincoln; Ben-Itzhak, Svetla. "NASA's head warned that China may try to claim the Moon – two space scholars explain why that's unlikely to happen". The Conversation. Retrieved July 11, 2022.
- "Satellite Database". Union of Concerned Scientists. Retrieved July 14, 2022.
- "Thomas Edison's Most Famous Inventions". Thomas A Edison Innovation Foundation. Archived from the original on March 16, 2016. Retrieved January 21, 2015.
- Benedetti, François (December 17, 2003). "100 Years Ago, the Dream of Icarus Became Reality". Fédération Aéronautique Internationale (FAI). Archived from the original on September 12, 2007. Retrieved August 15, 2007.
- Fraser, Gordon (2012). The Quantum Exodus: Jewish Fugitives, the Atomic Bomb, and the Holocaust. New York: Oxford University Press. ISBN 978-0-19-959215-9.
- 10 Little Americans. ISBN 978-0-615-14052-0. Retrieved September 15, 2014 – via Google Books.
- "NASA's Apollo technology has changed the history". Sharon Gaudin. July 20, 2009. Retrieved September 15, 2014.
- Sawyer, Robert Keith (2012). Explaining Creativity: The Science of Human Innovation. Oxford University Press. p. 256. ISBN 978-0-19-973757-4.
- WIPO (2022). Global Innovation Index 2022, 15th Edition. www.wipo.int. Global Innovation Index. World Intellectual Property Organization. doi:10.34667/tind.46596. ISBN 9789280534320. Retrieved November 16, 2022.
- "Visualizing America's Energy Use, in One Giant Chart". Visual Capitalist. May 6, 2020. Retrieved May 7, 2020.
- "What is the United States' share of world energy consumption?". U.S. Energy Information Administration. November 5, 2021.
- "EIA – Petroleum Basic Data". Eia.doe.gov. Retrieved March 30, 2012.
- US EPA, OAR (February 8, 2017). "Inventory of U.S. Greenhouse Gas Emissions and Sinks". US EPA. Retrieved December 3, 2020.
- "Railways – The World Factbook". The World Factbook. Central Intelligence Agency. Retrieved July 14, 2022.
- "Seasonally Adjusted Transportation Data". Washington, D.C.: Bureau of Transportation Statistics. 2021. Retrieved February 16, 2021.
- "Waterways – The World Factbook". The World Factbook. Central Intelligence Agency. Retrieved July 14, 2022.
- "Public Road and Street Mileage in the United States by Type of Surface". United States Department of Transportation. Archived from the original on January 2, 2015. Retrieved January 13, 2015.
- "China overtakes US in car sales". The Guardian. London. January 8, 2010. Retrieved July 10, 2011.
- "Fact #962: Vehicles per Capita: Other Regions/Countries Compared to the United States". Energy.gov. January 30, 2017. Retrieved January 23, 2021.
- "Vehicle Statistics: Cars Per Capita". Capitol Tires.
- Edwards, Chris (July 12, 2020). "Privatization". Downsizing the Federal Government. Cato Institute. Retrieved January 23, 2021.
- "Scheduled Passengers Carried". International Air Transport Association (IATA). 2011. Archived from the original on January 2, 2015. Retrieved February 17, 2012.
- "Preliminary World Airport Traffic and Rankings 2013—High Growth Dubai Moves Up to 7th Busiest Airport". March 31, 2014. Archived from the original on April 1, 2014. Retrieved May 17, 2014.
- "The Top 50 Container Ports". World Shipping Council. Washington, D.C. Retrieved July 14, 2022.
- Jin, Connie Hanzhang; Talbot, Ruth; Lo Wang, Hansi (August 13, 2021). "What The New Census Data Shows About Race Depends On How You Look At It". NPR.
- "Census Bureau's 2020 Population Count". United States Census. Retrieved April 26, 2021.
- "The World Factbook: United States". Central Intelligence Agency. Retrieved November 10, 2018.
- "Population Clock". www.census.gov.
- "Table MS-1. Marital Status of the Population 15 Years Old and Over, by Sex, Race and Hispanic Origin: 1950 to Present". Historical Marital Status Tables. U.S. Census Bureau. Retrieved September 11, 2019.
- Hamilton, Brady E.; Martin, Joyce A.; Osterman, Michelle J.K. (May 2021). Births: Provisional data for 2020 (PDF) (Report). Vol. Vital Statistics Rapid Release. Hyattsville, MD: National Center for Health Statistics. doi:10.15620/cdc:104993.
- "U.S. has world's highest rate of children living in single-parent households". Pew Research Center. Retrieved March 17, 2020.
- "Ancestry 2000" (PDF). U.S. Census Bureau. June 2004. Archived (PDF) from the original on December 4, 2004. Retrieved December 2, 2016.
- "The Chance That Two People Chosen at Random Are of Different Race or Ethnicity Groups Has Increased Since 2010".
- "Table 52. Population by Selected Ancestry Group and Region: 2009" (PDF). U.S. Census Bureau. 2009. Archived from the original (PDF) on December 25, 2012. Retrieved February 11, 2017.
- "Frequently Requested Statistics on Immigrants and Immigration in the United States". Migration Policy Institute. March 14, 2019.
- "Key findings about U.S. immigrants". Pew Research Center. June 17, 2019.
- Jens Manuel Krogstad (October 7, 2019). "Key facts about refugees to the U.S." Pew Research Center.
- "States Where English Is the Official Language". The Washington Post. August 12, 2014. Retrieved September 12, 2020.
- "The Constitution of the State of Hawaii, Article XV, Section 4". Hawaii Legislative Reference Bureau. November 7, 1978. Archived from the original on July 24, 2013. Retrieved June 19, 2007.
- Chapel, Bill (April 21, 2014). "Alaska OKs Bill Making Native Languages Official". NPR.
- "South Dakota recognizes official indigenous language". Argus Leader. Retrieved March 26, 2019.
- "Translation in Puerto Rico". Puerto Rico Channel. Archived from the original on December 30, 2013. Retrieved December 29, 2013.
- Bureau, U.S. Census. "American FactFinder—Results". Archived from the original on February 12, 2020. Retrieved May 29, 2017.
- "Foreign Language Enrollments in K–12 Public Schools" (PDF). American Council on the Teaching of Foreign Languages (ACTFL). February 2011. Archived from the original (PDF) on April 8, 2016. Retrieved October 17, 2015.
- Goldberg, David; Looney, Dennis; Lusin, Natalia (February 2015). "Enrollments in Languages Other Than English in United States Institutions of Higher Education, Fall 2013" (PDF). Modern Language Association. Retrieved May 20, 2015.
- Diamant, Jeff (January 3, 2023). "Faith on the Hill: The religious composition of the 118th Congress". Pew Research Center. Retrieved January 4, 2023.
- Inglehart, Ronald (September–October 2020). "Giving Up on God". Foreign Affairs. ISSN 0015-7120. Retrieved January 1, 2023.
- Nadeem, Reem (September 13, 2022). "Modeling the Future of Religion in America". Pew Research Center. Retrieved January 1, 2023.
- Campbell, David; Layman, Geoffrey; Green, John Clifford. Secular Surge: A New Fault Line in American Politics. p. Introduction. ISBN 978-1-108-92334-7. OCLC 1237630231.
American society is rapidly secularizing–a radical departure from its historically high level of religiosity...
- Thompson, Derek (September 26, 2019). "Three Decades Ago, America Lost Its Religion. Why?". The Atlantic. Retrieved October 2, 2022.
- Jones, Jeffrey (June 17, 2022). "Belief in God in U.S. Dips to 81%, a New Low". Gallup. Retrieved January 1, 2023.
- Shimron, Yonat (December 17, 2021). "More Americans are becoming secular, poll says". The Washington Post. Retrieved January 1, 2023.
- Jones, Jeffrey (December 21, 2022). "In U.S., Childhood Churchgoing Habits Fade in Adulthood". Gallup.com. Retrieved January 1, 2023.
- Staff (January 20, 2022). "The Decline in Church Attendance in COVID America". Institute for Family Studies. Retrieved February 3, 2023.
- ANALYSIS (December 19, 2011). "Global Christianity". Pewforum.org. Archived from the original on July 30, 2013. Retrieved August 17, 2012.
- "Mississippians Go to Church the Most; Vermonters, Least". Gallup. February 17, 2010. Retrieved January 13, 2014.
- "America's Changing Religious Landscape". Pew Research Center: Religion & Public Life. May 12, 2015.
- Jones, Jeffrey M. (March 29, 2021). "U.S. Church Membership Falls Below Majority for First Time". Gallup.com. Retrieved April 5, 2021.
- Gabbatt, Adam (April 5, 2021). "'Allergic reaction to US religious right' fueling decline of religion, experts say". The Guardian. Retrieved April 5, 2021.
- McCarthy, Justin (July 8, 2019). "U.S. Confidence in Organized Religion Remains Low". Gallup.com. Retrieved January 1, 2023.
- "First Amendment". Constitution Annotated. United States Congress.
- "United States—Urban/Rural and Inside/Outside Metropolitan Area". U.S. Census Bureau. Archived from the original on April 3, 2009. Retrieved September 23, 2008.
- "Table 1: Annual Estimates of the Resident Population for Incorporated Places Over 100,000, Ranked by July 1, 2008 Population: April 1, 2000 to July 1, 2008" (PDF). 2008 Population Estimates. U.S. Census Bureau, Population Division. July 1, 2009. Archived from the original (PDF) on December 7, 2009.
- "Counties in South and West Lead Nation in Population Growth". The United States Census Bureau. April 18, 2019. Retrieved August 29, 2020.
- "Ages for Compulsory School Attendance ..." U.S. Dept. of Education, National Center for Education Statistics. Retrieved June 10, 2007.
- "Educational Attainment in the United States: 2003" (PDF). U.S. Census Bureau. Retrieved August 1, 2006.
- For more detail on U.S. literacy, see A First Look at the Literacy of America's Adults in the 21st century, U.S. Department of Education (2003).
- "QS World University Rankings 2022". QS World University Rankings. Quacquarelli Symonds. June 8, 2021. Retrieved July 14, 2022.
- Pannoni, Alexandra; Kerr, Emma (July 14, 2020). "Everything You Need to Know About Community Colleges: FAQ". U.S. News & World Report. Retrieved July 9, 2022.
- Rushe, Dominic (September 7, 2018). "The US spends more on education than other countries. Why is it falling behind?". The Guardian. ISSN 0261-3077. Retrieved August 29, 2020.
- "Fast Facts: Expenditures". nces.ed.gov. April 2020. Retrieved August 29, 2020.
- "U.S. education spending tops global list, study shows". CBS. AP. June 25, 2013. Retrieved October 5, 2013.
- "The Biden administration cancelled $9.5B in student loan debt. Here's who it affects". USAFacts. Retrieved July 15, 2022.
- Hess, Abigail Johnson (December 22, 2020). "U.S. student debt has increased by more than 100% over the past 10 years". CNBC. Retrieved January 8, 2022.
- Dickler, Jessica; Nova, Annie (May 6, 2022). "This is how student loan debt became a $1.7 trillion crisis". CNBC. Retrieved July 8, 2022.
- "Texas Medical Center, largest medical complex in the world, reaches 98 percent ICU capacity". Newsweek. August 19, 2020.
- "Life Expectancy in the United States Declines, Centers for Disease Control and Prevention, National Center for Health Statistics". www.cdc.gov. August 31, 2022. Retrieved September 3, 2022.
- Noguchi, Yuki (December 22, 2022). "American life expectancy is now at its lowest in nearly two decades". NPR. Retrieved December 27, 2022.
- "Mortality in the United States, 2017". www.cdc.gov. November 29, 2018. Retrieved December 27, 2018.
- Bernstein, Lenny (November 29, 2018). "U.S. life expectancy declines again, a dismal trend not seen since World War I". The Washington Post. Retrieved December 27, 2018.
- Achenbach, Joel (November 26, 2019). "'There's something terribly wrong': Americans are dying young at alarming rates". The Washington Post. Retrieved December 19, 2019.
- "New International Report on Health Care: U.S. Suicide Rate Highest Among Wealthy Nations | Commonwealth Fund". www.commonwealthfund.org. January 30, 2020. Retrieved March 17, 2020.