**Historical Overview:**
– Indigenous peoples migrated to North America over 12,000 years ago.
– European colonization by Spain, France, and Britain led to settlements and conflicts.
– American Revolution, Declaration of Independence, and Treaty of Paris (1783).
– Westward expansion, manifest destiny, and conflicts with Native Americans.
– Civil War, Emancipation Proclamation, and Reconstruction era.
**Government and Politics:**
– U.S. is a presidential constitutional republic with three branches of government.
– Bicameral national legislature with House of Representatives and Senate.
– States and territories have substantial autonomy.
– Political culture emphasizes liberty, equality, individualism, and limited government.
– Operates as a de facto two-party system with the Democratic and Republican parties.
**Economic Development and Status:**
– U.S. has had the largest nominal GDP since 1890.
– Accounts for 15% of the global economy in 2023.
– Possesses the largest wealth and highest median income per capita.
– Ranks high in economic competitiveness, innovation, and human rights.
– Founding member of World Bank, IMF, NATO, and other international organizations.
**Geography, Climate, and Biodiversity:**
– U.S. ranks as the world’s third-largest country by total area.
– Diverse geographical features from coastal plains to mountains, rivers, prairies, and deserts.
– Varied climate types ranging from humid continental to tropical.
– Home to diverse fauna and flora, with extensive national parks and conservation areas.
– Environmental issues include debates on resources, pollution, biodiversity, and climate change.
**Modern Developments and Contemporary Issues:**
– Post-World War II rise as a superpower and Cold War dominance.
– Longest economic expansion in the 1990s and technological advances.
– Gulf War, September 11 attacks, war on terror, and Great Recession.
– Political polarization, cultural debates, and the January 2021 Capitol attack.
– Ongoing debates on cultural issues, economic growth, and political stability.
The United States of America (USA or U.S.A.), commonly known as the United States (US or U.S.) or America, is a country primarily located in North America. It is a federation of 50 states, a federal capital district (Washington, D.C.), and 326 Indian reservations. Outside the union of states, it asserts sovereignty over five major unincorporated island territories and various uninhabited islands. The country has the world's third-largest land area, second-largest exclusive economic zone, and third-largest population, exceeding 334 million.
United States of America | |
|---|---|
| Motto: "In God We Trust" Other traditional mottos:
| |
| Anthem: "The Star-Spangled Banner" | |
   | |
| Capital | Washington, D.C. 38°53′N 77°1′W / 38.883°N 77.017°W |
| Largest city | New York City 40°43′N 74°0′W / 40.717°N 74.000°W |
| Official languages | None at the federal level |
| National language | English |
| Ethnic groups (2020) | By race:
By origin:
|
| Religion (2022) |
|
| Demonym(s) | American |
| Government | Federal presidential republic |
| Joe Biden | |
| Kamala Harris | |
| Mike Johnson | |
| John Roberts | |
| Legislature | Congress |
| Senate | |
| House of Representatives | |
| Independence from Great Britain | |
| July 4, 1776 | |
| March 1, 1781 | |
| September 3, 1783 | |
| June 21, 1788 | |
| Area | |
• Total area | 3,796,742 sq mi (9,833,520 km2) (3rd[d]) |
• Water (%) | 7.0 (2010) |
• Land area | 3,531,905 sq mi (9,147,590 km2) (3rd) |
| Population | |
• 2023 estimate |  334,914,895 |
• 2020 census | 331,449,281 (3rd) |
• Density | 87/sq mi (33.6/km2) (185th) |
| GDP (PPP) | 2024 estimate |
• Total |  $28.781 trillion (2nd) |
• Per capita | $85,373 (8th) |
| GDP (nominal) | 2024 estimate |
• Total | $28.781 trillion (1st) |
• Per capita | $85,373 (6th) |
| Gini (2020) |  39.4medium |
| HDI (2022) | 0.927 very high (20th) |
| Currency | U.S. dollar ($) (USD) |
| Time zone | UTC−4 to −12, +10, +11 |
• Summer (DST) | UTC−4 to −10 |
| Date format | mm/dd/yyyy |
| Driving side | right |
| Calling code | +1 |
| ISO 3166 code | US |
| Internet TLD | .us |
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Paleo-Indians migrated across the Bering land bridge more than 12,000 years ago. British colonization led to the first settlement of the Thirteen Colonies in Virginia in 1607. Clashes with the British Crown over taxation and political representation sparked the American Revolution, with the Second Continental Congress formally declaring independence on July 4, 1776. Following its victory in the Revolutionary War (1775–1783), the country continued to expand across North America. As more states were admitted, sectional division over slavery led to the secession of the Confederate States of America, which fought the remaining states of the Union during the 1861–1865 American Civil War. With the Union's victory and preservation, slavery was abolished nationally. By 1890, the United States had established itself as a great power. After Japan's attack on Pearl Harbor in December 1941, the U.S. entered World War II. The aftermath of the war left the U.S. and the Soviet Union as the world's two superpowers and led to the Cold War, during which both countries engaged in a struggle for ideological dominance and international influence. Following the Soviet Union's collapse and the end of the Cold War in 1991, the U.S. emerged as the world's sole superpower.
The U.S. national government is a presidential constitutional republic and liberal democracy with three separate branches: legislative, executive, and judicial. It has a bicameral national legislature composed of the House of Representatives, a lower house based on population; and the Senate, an upper house based on equal representation for each state. Substantial autonomy is given to states and several territories, with a political culture that emphasizes liberty, equality under the law, individualism, and limited government.
One of the world's most developed countries, the United States has had the largest nominal GDP since about 1890 and accounted for 15% of the global economy in 2023. It possesses by far the largest amount of wealth of any country and has the highest disposable household income per capita among OECD countries. The U.S. ranks among the world's highest in economic competitiveness, productivity, innovation, human rights, and higher education. Its hard power and cultural influence have a global reach. The U.S. is a founding member of the World Bank, IMF, Organization of American States, NATO, and World Health Organization, as well as a permanent member of the UN Security Council.