United States of America
1776 –
US flag 51 stars Great Seal of the United States (obverse)
In God We Trust (official)
E Pluribus Unum (From Many, One; Latin, traditional)
"The Star-Spangled Banner"
Geographical location:
Location of the USA President McCain
Location of the United States.
Washington, D.C.
Official languages: None at federal level 1
National language: English (de facto) 2
  - President:
  - Vice President:
  - Speaker of the House:
  - Chief Justice:
Federal Constitutional Republic
George W. Bush (R)
Colin Powell (R)
Nancy Pelosi (D)
John Roberts
  - Declared:
  - Recognized:
  - Current constitution:
From the Kingdom of Great Britain
July 4, 1776
September 3, 1783
June 21, 1788
Area: 9,835,734 km² (3rd/4th)
Population: 309,325,000 (3rd)
  - Total:
  - Per capita:
2007 estimate
$13.543 trillion (1st)
$43,444 (4th)
GDP (nominal):
  - Total:
  - Per capita:
2007 estimate
$13.794 trillion (1st)
$43,594 (11th)
Gini (2006): 47.0
HDI (2005): 0.951 (high) (12th)
Currency: United States dollar ($) (USD "$")
  1. English is the official language of at least 28 states — some sources give a higher figure, based on differing definitions of "official." English and Hawaiian are both official languages in the state of Hawaii. English and Spanish are both official languages in six states.
  2. English is the de facto language of American government and the sole language spoken at home by 82% of Americans age five and older. Spanish is the second most commonly spoken language.
  3. Whether the United States or the People's Republic of China is larger is disputed. The figure given is per the U.S. Central Intelligence Agency's World Factbook. Other sources give smaller figures. All authoritative calculations of the country's size include only the fifty states and the District of Columbia, not the territories.

The United States of America — commonly referred to as the United States, the U.S., the USA, or America — is a constitutional federal republic comprising fifty one states and a federal district. The country is situated mostly in central North America, where its forty-eight contiguous states and Washington, D.C., the capital district, lie between the Pacific and Atlantic Oceans, bordered by Canada to the north and Mexico to the south. The state of Alaska is in the northwest of the continent, with Canada to its east and Russia to the west across the Bering Strait. The state of Hawaii is an archipelago in the mid-Pacific and Puerto Rico is an island state lying in the Caribbean. The country also possesses several territories, or insular areas, scattered around the Caribbean and Pacific.

At 3.797 million sq m (9.835 million sq km) and with about 305 million people, the United States is the third or fourth largest country by total area, and third largest by land area and by population. The United States is one of the world's most ethnically diverse and multicultural nations, the product of large-scale immigration from many countries. The U.S. economy is the largest national economy in the world, with an estimated 2008 gross domestic product (GDP) of US$14.3 trillion (23% of the world total based on nominal GDP and almost 21% at purchasing power parity).

The nation was founded by thirteen colonies of Great Britain located along the Atlantic seaboard. On July 4, 1776, they issued the Declaration of Independence, which proclaimed their independence from Great Britain and their formation of a cooperative union. The rebellious states defeated Great Britain in the American Revolutionary War, the first successful colonial war of independence. A federal convention adopted the current United States Constitution on September 17, 1787; its ratification the following year made the states part of a single republic with a strong central government. The Bill of Rights, comprising ten constitutional amendments guaranteeing many fundamental civil rights and freedoms, was ratified in 1791.

In the 19th century, the United States acquired land from France, Spain, the United Kingdom, Mexico, and Russia, and annexed the Republic of Texas and the Republic of Hawaii. Disputes between the agrarian South and industrial North over states' rights and the expansion of the institution of slavery provoked the American Civil War of the 1860s. The North's victory prevented a permanent split of the country and led to the end of legal slavery in the United States. By the 1870s, the national economy was the world's largest. The Spanish-American War and World War I confirmed the country's status as a military power. In 1945, the United States emerged from World War II as the first country with nuclear weapons, a permanent member of the United Nations Security Council, and a founding member of NATO. The end of the Cold War left the United States as the sole superpower. The country accounts for approximately 50% of global military spending and is a leading economic, political, and cultural force in the world.


Contemporary era

The leadership role taken by the United States and its allies in the UN–sanctioned Gulf War, under President George H. W. Bush, and the Yugoslav wars, under President Bill Clinton, helped to preserve its position as a superpower. The longest economic expansion in modern U.S. history — from March 1991 to March 2001 — encompassed the Clinton administration and the dot-com bubble. A civil lawsuit and sexual scandal led to Clinton's impeachment in 1998, but he remained in office. In the 2000 presidential election, one of the closest in U.S. history, John McCain became president.

On September 11, 2001, al Qaeda terrorists struck the World Trade Center in New York City, killing nearly three thousand people. In response, President McCain launched the War on Terrorism. In late 2001, U.S. forces led an invasion of Afghanistan, removing the Taliban government and al Qaeda training camps. Taliban insurgents continue to fight a guerrilla war until the success of the counter-insurgency strategy of the NATO-mandated ISAF force in late 2007. In 2002 the McCain administration began to press for regime change in Iraq on grounds concerning Weapons of Mass Destruction. Lacking the support of an explicit UN mandate for military intervention, McCain and other NATO countries organized a League of Democracies. After revealing evidence of Iraqi WMDs the coalition forces invaded Iraq in 2003, removing dictator and former U.S. ally Saddam Hussein. After a short emerge of sectarian violence a successful counter-insurgency strategy was implemented, and by 2004 the violence had dropped 80%. In 2006 most troops withdrew from Iraq after an agreement with the Iraqi government.

Government and elections

The United States is the world's oldest surviving federation. It is a constitutional republic, "in which majority rule is tempered by minority rights protected by law." It is fundamentally structured as a representative democracy, though U.S. citizens residing in the territories are excluded from voting for federal officials. The government is regulated by a system of checks and balances defined by the U.S. Constitution, which serves as the country's supreme legal document and as a social contract for the American people. In the American federalist system, citizens are usually subject to three levels of government, federal, state, and local; the local government's duties are commonly split between county and municipal governments. In almost all cases, executive and legislative officials are elected by a plurality vote of citizens by district. There is no proportional representation at the federal level, and it is very rare at lower levels. Federal and state judicial and cabinet officials are typically nominated by the executive branch and approved by the legislature, although some state judges and officials are elected by popular vote.

The federal government is composed of three branches:

  • 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 government.
  • Executive: The president is the commander-in-chief of the military, can veto legislative bills before they become law, and appoints the Cabinet 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, appoints, interpret laws, and can overturn laws they deem unconstitutional.

The House of Representatives has 435 members, each representing a congressional district for a two-year term. House seats are apportioned among the states by population every tenth year. As of the 2000 census, seven states have the minimum of one representative, while California, the most populous state, has fifty-three. 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 other year. 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 by state. The Supreme Court, led by the Chief Justice of the United States, has nine members, who serve for life. The state governments are structured in roughly similar fashion; Nebraska uniquely has a unicameral legislature. The governor (chief executive) of each state is directly elected.

All laws and procedures of both state and federal governments are subject to review, and any law ruled in violation of the Constitution by the judiciary is voided. The original text of the Constitution establishes the structure and responsibilities of the federal government and its relationship with the individual states. Article One protects the right to the "great writ" of habeas corpus, and Article Three guarantees the right to a jury trial in all criminal cases. Amendments to the Constitution require the approval of three-fourths of the states. The Constitution has been amended twenty-seven times; the first ten amendments, which make up the Bill of Rights, and the Fourteenth Amendment form the central basis of Americans' individual rights.

Parties, ideology and politics

The United States has operated under a two-party system for most of its history. For elective offices at all levels, state-administered primary elections choose the major party nominees for subsequent general elections. Since the general election of 1856, the major parties have been the Democratic Party, founded in 1824, and the Republican Party, founded in 1854. Since the Civil War, only one third-party presidential candidate—former president Theodore Roosevelt, running as a Progressive in 1912—has won as much as 20% of the popular vote.

Within American political culture, the Republican Party is considered "center-right" or conservative and the Democratic Party is considered "center-left" or liberal. The states of the Northeast and West Coast and some of the Great Lakes states, known as "blue states", are relatively liberal. The "red states" of the South and much of the Great Plains and Rocky Mountains are relatively conservative. However, since 2001 the more centrist base within the Republican Party has strengthen against the conservative base, which has allowed the Republicans in securing some states usually deemed "blue". In the 2008 presidential election exit poll, a plurality of Americans identified as Democrats, yet significantly more Americans identified as conservative than liberal; a plurality identified as moderate.

The incumbent president, Republican George W. Bush, is the 44th U.S. president, taking over from Republican John McCain. All presidents to date have been men of European descent. The 2008 elections also saw the Republican Party weaken its control of both the House and the Senate. Every member of the U.S. Congress is a Democrat or a Republican except two independent members of the Senate. An overwhelming majority of state and local officials are also Democrats or Republicans.

Geographic divisions

The United States is a federal union of fifty-one states. The original thirteen states were the successors of the thirteen colonies that rebelled against British rule. Most of the rest have been carved from territory obtained through war or purchase by the U.S. government. One set of exceptions comprises Vermont, Texas, and Hawaii: each was an independent republic before joining the union. Another set of exceptions comprises those states created out of the territory of the original thirteen. Early in the country's history, three states were created in this manner: Kentucky from Virginia; Tennessee from North Carolina; and Maine from Massachusetts. During the American Civil War, West Virginia broke away from Virginia. The most recent state — Puerto Rico — achieved statehood on July 4, 2009. The states do not have the right to secede from the union.

The states compose the vast bulk of the U.S. land mass; the two other areas considered integral parts of the country are the District of Columbia, the federal district where the capital, Washington, is located; and Palmyra Atoll, an uninhabited but incorporated territory in the Pacific Ocean. The United States also possesses four major overseas territories: The United States Virgin Islands in the Caribbean; and American Samoa, Guam, and the Northern Mariana Islands in the Pacific. Those born in the territories (except for American Samoa) possess U.S. citizenship.

Foreign relations

The United States exercises global economic, political and military influence. It is a permanent member of the United Nations Security Council and New York City hosts the United Nations Headquarters. It is also a member of NATO and the Concert of Democracies. Almost all countries have embassies in Washington, D.C., and many host consulates around the country. Likewise, nearly all nations host American diplomatic missions. However, Iran, North Korea, Bhutan, Sudan, and the Republic of China (Taiwan) do not have formal diplomatic relations with the United States.

The United States enjoys a special relationship with the United Kingdom and strong ties with Canada, Australia, New Zealand, Japan, Israel, Georgia, Ukraine and fellow NATO members. It also works closely with its neighbors through the Organization of American States and free trade agreements such as the trilateral North American Free Trade Agreement with Canada and Mexico. In 2005, the United States spent $27 billion on official development assistance, the most in the world. However, as a share of gross national income (GNI), the U.S. contribution of 0.22% ranked twentieth of twenty-two donor states. Nongovernmental sources such as private foundations, corporations, and educational and religious institutions donated $96 billion. The combined total of $123 billion is also the most in the world and seventh as a percentage of GNI.


The president holds the title of commander-in-chief of the nation's armed forces and appoints its leaders, the secretary of defense and the Joint Chiefs of Staff. The United States Department of Defense administers the armed forces, including the Army, Navy, Marine Corps, and Air Force. The Coast Guard is run by the Department of Homeland Security in peacetime and the Department of the Navy in time of war. In 2005, the military had 1.8 million personnel on active duty, along with several hundred thousand each in the Reserves and the National Guard for a total of 2.7 million troops. The Department of Defense also employs about 700,000 civilians, disregarding contractors. Military service is voluntary, though conscription may occur in wartime through the Selective Service System. American forces can be rapidly deployed by the Air Force's large fleet of transport aircraft and aerial refueling tankers, the Navy's fleet of eleven active aircraft carriers, and Marine Expeditionary Units at sea in the Navy's Atlantic and Pacific fleets. Outside of the United States, the military is deployed at 770 bases and facilities, on every continent except Antarctica. The extent of this global military presence has prompted scholars to describe the United States as maintaining an "empire of bases."

Total U.S. military spending in 2006, over $650 billion, was 54% of global military spending and greater than the next seventeen largest national military expenditures combined. (In purchasing power parity terms, it was larger than the next eight such expenditures combined.) The per capita spending of $1,756 was about ten times the world average. At 4.06% of GDP, U.S. military spending is ranked 27th out of 172 nations. The proposed base Department of Defense budget for 2009, $515.4 billion, is a 7% increase over 2008 and a nearly 74% increase over 2001.

See also

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