United States
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- This article is about the country in North America. For other uses of terms that redirect here, see US (disambiguation), USA (disambiguation) and United States (disambiguation).
</div> </div> The United States of America, also known as the United States, the U.S., the US , the U.S.A., the USA , the U.S. of A., The States, and America, is a country in North America that extends from the Atlantic Ocean to the Pacific Ocean and shares land borders with Canada and Mexico. The United States is a federal constitutional republic, with its capital in Washington, D.C.
At over 3.7 million square miles (over 9.5 million km²), the U.S. (including its non-contiguous and overseas states and territories) is the third largest country by total area. It is the world's third most populous nation, with over 300 million people.
American military, economic, cultural, and political influence increased through the 19th and 20th centuries. With the collapse of the Soviet Union at the end of the Cold War, the nation emerged as the world's sole remaining superpower,<ref>History and the Hyperpower by Eliot A. Cohen. July/August 2004. Council on Foreign Relations. URL accessed July 14, 2006.</ref> and today, the United States plays a major role in world affairs.
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Name
- See also: List of meanings of countries' names
The earliest known use of the name America is from 1507, when a globe and a large map created by the German cartographer Martin Waldseemüller in Saint-Dié-des-Vosges described the combined continents of the North and South Americas. Although the origin of the name is uncertain,<ref>Theories on the origin of America's name</ref> the most widely held belief is that expressed in an accompanying book, Cosmographiae Introductio, which explains it as a feminized version of the Latin name of Italian explorer Amerigo Vespucci (Americus Vespucius); in Latin, the other continents' names were all feminine. Vespucci theorized, correctly, that Christopher Columbus, on reaching islands in the Caribbean Sea in 1492, had come not to India but to a "New World".
The Americas were also known as Columbia, after Columbus, prompting the name District of Columbia for the land set aside as the U.S. capital. Columbia remained a popular name for the United States until the early 20th century, when it fell into relative disuse; but it is still used poetically and appears in various names and titles. One female personification of the country is called Columbia; she is similar to Britannia.<ref>http://www.nasa.gov/columbia/home/index.html</ref><ref>http://www.museum.tv/archives/etv/C/htmlC/columbiabroa/columbiabroa.htm</ref><ref>http://www.reelclassics.com/Studios/Columbia/columbia.htm</ref><ref>http://memory.loc.gov/cocoon/ihas/loc.natlib.ihas.200000004/default.html</ref> Columbus Day is a holiday in the U.S. and other countries in the Americas commemorating Columbus' October 1492 landing.
The term "united States of America" was first used officially in the Declaration of Independence, adopted on July 4 1776. On November 15 1777, the Second Continental Congress adopted the Articles of Confederation, the first of which stated "The Stile [sic] of this Confederacy shall be 'The United States of America.'" The name was originally proposed by Thomas Paine.
The adjectival and demonymic forms for the United States are American, although this term can also refer to other inhabitants of either North or South America.
Geography
The United States is the world's third largest country by total area, and the second largest by land area alone, after Russia.<ref>Field Listing- Area. 2 November 2006. CIA World Factbook. URL accessed 13 November 2006.</ref> Its contiguous portion is bounded by the North Atlantic Ocean to the east, the North Pacific Ocean to the west, Mexico and the Gulf of Mexico to the south, and Canada to the north. The state of Alaska also borders Canada, with the Pacific Ocean to its south and the Arctic Ocean to its north. West of Alaska, across the narrow Bering Strait, is Russia. The state of Hawaii occupies an archipelago in the Pacific Ocean, southwest of the North American mainland.
Terrain
The U.S. has an extremely varied geography, particularly in the West. The eastern seaboard has a coastal plain which is widest in the south and narrows in the north. The coastal plain does not exist north of New Jersey, although there are glacial outwash plains on Long Island, Martha's Vineyard, and Nantucket. In the extreme southeast, Florida is home to the ecologically unique Everglades.
Beyond the coastal plain, the rolling hills of the Piedmont region end at the Appalachian Mountains, which rise above 6,000 feet (1,830 m) in North Carolina, Tennessee, and New Hampshire. From the west slope of the Appalachians, the Interior Plains of the Midwest are relatively flat and are the location of the Great Lakes as well as the Mississippi-Missouri River, the world's 4th longest river system.<ref>Mississippi River. 2004. Visit Bemidji- First City on the Mississippi. URL accessed May 3, 2006.</ref> West of the Mississippi River, the Interior Plains slope uphill and blend into the vast and often featureless Great Plains.
The abrupt rise of the Rocky Mountains, at the western edge of the Great Plains, extends north to south across the continental U.S., reaching altitudes over 14,000 feet (4,270 m) in Colorado.<ref>Peakbagger.com, Colorado 14,000-foot Peaks, URL accessed May 3, 2006.</ref> In the past, the Rocky Mountains had a higher level of volcanic activity; nowadays, the range only has one area of volcanism (the supervolcano underlying Yellowstone National Park in Wyoming, possibly the world's largest volcano), although rift volcanism has occurred relatively recently near the Rockies' southern margin in New Mexico.<ref>Smithsonian Institution Global Volcanism Program, New Mexico volcanoes, URL accessed August 26, 2006.</ref>
Alaska has numerous mountain ranges, including Mount McKinley (Denali), the highest peak in North America. Numerous volcanoes can be found throughout the Alexander and Aleutian Islands extending south and west of the Alaskan mainland.
The Hawaiian islands are tropical, volcanic islands extending over 1,500 miles (2,400 km), and consisting of six larger islands and another dozen smaller ones that are inhabited.
Climate
Due to its large size and wide range of geographic features, the United States contains examples of nearly every global climate. The climate is temperate in most areas, tropical in Hawaii and southern Florida, polar in Alaska, semiarid in the Great Plains west of the 100th meridian, Mediterranean in coastal California and arid in the Great Basin. Its comparatively generous climate contributed (in part) to the country's rise as a world power, with infrequent severe drought in the major agricultural regions, a general lack of widespread flooding, and a mainly temperate climate that receives adequate precipitation.
History
Native Americans
Before the European colonization of the Americas, a process that began at the end of the 15th century, the present-day continental U.S. was inhabited exclusively by various indigenous tribes, including Alaskan natives, who migrated to the continent over a period that may have begun 35,000 years ago and may have ended as recently as 11,000 years ago.<ref>"Paleoamerican Origins". 1999. Smithsonian Institution. Accessed 2 May 2006.</ref>
European colonization
The first confirmed European landing in the present-day United States was by Christopher Columbus, who visited Puerto Rico on November 19, 1493, during his second voyage. San Juan, the United States' first European settlement was founded there on August 8, 1508 by Juan Ponce de León. Ponce de León went on to become the first confirmed European to arrive in the continental US when he landed in Florida on April 2, 1513. Florida was home to the continental United States' earliest European colonies; these were Pensacola (founded by Tristán de Luna y Arellano in 1559), Fort Caroline (by René Goulaine de Laudonnière in 1564), and St. Augustine (by Pedro Menéndez de Avilés in 1565), the last of which is the only one which was continuously inhabited since its foundation.
The French colonized some of the northeastern portions, and the Spanish colonized most of the southern and western United States. The first successful English settlement was at Jamestown, Virginia, in 1607, followed in 1620 by the Pilgrims' landing at Plymouth, Massachusetts, then the arrival of the colony of Massachusetts Bay, started by the Puritans. In 1609 and 1617, respectively, the Dutch settled in part of what became New York and New Jersey. In 1638, the Swedes founded New Sweden, in part of what became Delaware, New Jersey, and Pennsylvania after passing through Dutch hands. Throughout the 17th and early 18th centuries, England (and later Great Britain) established new colonies, took over Dutch colonies, and split others. With the division of the Carolinas in 1729, and the colonization of Georgia in 1732, the British colonies in North America—excluding present-day Canada, and the loyal colonies of East and West Florida—numbered thirteen.
American Revolution
Tensions between American colonials and the British during the revolutionary period of the 1760s and 1770s led to open military conflict in 1775. George Washington commanded the Continental Army during the American Revolutionary War (1775–1783) as the Second Continental Congress adopted the Declaration of Independence on July 4, 1776. The Congress had been formed to confront British actions and created the Continental Army, but it did not have the authority to levy taxes or make federal laws. In 1777, the Congress adopted the Articles of Confederation, uniting the states under a weak federal government, which operated from 1781 until 1788, when enough states had ratified the United States Constitution. The Constitution, which strengthened the union and the federal government, has since remained the supreme law of the land<ref>Yanak, Ted and Cornelison, Pam. The Great American History Fact-finder: The Who, What, Where, When, and Why of American History. Page 114. Houghton Mifflin; 2nd Updated edition: 27 August 2004. ISBN 0-618-43941-2</ref> and holds the record for the set of laws to stay in effect the longest in the world.
Westward expansion
From 1803 to 1848, the size of the new nation nearly tripled as settlers (many embracing the concept of Manifest Destiny as an inevitable consequence of American exceptionalism) pushed beyond national boundaries even before the Louisiana Purchase.<ref>Manifest Destiny- An interpretation of How the West was Won. Crossroads of Earth Resources and Society. URL accessed on 4 May 2006.</ref> The expansion was tempered somewhat by the stalemate in the War of 1812, but it was subsequently reinvigorated by victory in the Mexican-American War in 1848.
Between 1830-1880 up to 40 million American Buffalo were slaughtered for skins and meat, and to aid railway expansion. The expansion of the railways reduced transit times for both goods and people, made westward expansion less arduous for the pioneers, and increased conflicts with the Indians over the land and its uses. The loss of the buffalo, a primary resource for the plains Indians, added to the pressures on native cultures and individuals for survival.
Civil War
As new territories were being incorporated, the nation was divided over the issue of states' rights, the role of the federal government, and—by the 1820s—the expansion of slavery, which had been legal in all thirteen colonies but was rarer in the north, where it was abolished by 1804. The Northern states were opposed to the expansion of slavery whereas the Southern states saw the opposition as an attack on their way of life, since their economy was dependent on slave labor. The failure to permanently resolve these issues led to the Civil War, following the secession of many slave states in the South to form the Confederate States of America after the 1860 election of Abraham Lincoln.<ref>Morrison, Michael A Slavery and the American West: The Eclipse of Manifest Destiny and the Coming of the Civil War. Page 176. University of North Carolina Press. ISBN 0-8078-4796-8.</ref> The 1865 Union victory in the Civil War effectively ended slavery and settled the question of whether a state had the right to secede. The event was a major turning point in American history, with an increase in federal power.<ref>De Rosa, Marshall L. The Politics of Dissolution: The Quest for a National Identity and the American Civil War. Page 266. Transaction Publishers: 1 January 1997. ISBN 1-56000-349-9</ref>
Reconstruction and industrialization
After the Civil War, an unprecedented influx of immigrants, who helped to provide labor for American industry and create diverse communities in undeveloped areas—together with high tariff protections, national infrastructure building, and national banking regulations—hastened the country's rise to international power. The growing power of the United States enabled it to acquire new territories, including the annexation of Puerto Rico after victory in the Spanish-American War,<ref>Spielvogel, Jackson J. Western Civilization: Volume II: Since 1500. Page 708. Wadsworth Publishing: 10 January 2005. ISBN 0-534-64604-2</ref> which marked the debut of the United States as a major world power.
World Wars I and II
At the start of the World War I in 1914, the United States remained neutral. In 1917, however, the United States joined the Allied Powers, helping to turn the tide against the Central Powers. For historical reasons, American sympathies were very much in favor of the British and French, even though a sizable number of citizens, mostly Irish and German, were opposed to intervention.<ref>Eric Foner and John A. Garraty, The Reader's Companion to American History. Page 576. 21 October 1991. Houghton Mifflin. ISBN 0-395-51372-3.</ref> After the war, the Senate did not ratify the Treaty of Versailles because of a fear that it would pull the United States into European affairs. Instead, the country pursued a policy of unilateralism that bordered at times on isolationism.<ref>McDuffie, Jerome, Piggrem, Gary Wayne, and Woodworth, Steven E. U.S. History Super Review. Page 418. Research & Education Association: 21 June 2005. ISBN 0-7386-0070-9</ref>
During most of the 1920s, the United States enjoyed a period of unbalanced prosperity as farm prices fell and industrial profits grew. A rise in debt and an inflated stock market culminated in a crash in 1929, triggering the Great Depression. After his election as President in 1932, Franklin Delano Roosevelt instituted his plan for a New Deal, which increased government intervention in the economy in response to the Great Depression.
The nation did not fully recover until 1941, when the United States was driven to join the Allies against the Axis Powers after a surprise attack on Pearl Harbor by Japan. World War II was the costliest war in economic terms in American history,<ref>World War II By The Numbers. The National WWII Museum, New Orleans. Last accessed October 24, 2006.</ref><ref>More costly than 'the war to end all wars'. David R. Francis, Christian Science Monitor. August 29, 2005. Last accessed October 24, 2006.</ref> but it helped to pull the economy out of depression because the required production of military materiel provided much-needed jobs, and women entered the workforce in large numbers for the first time. During this war, scientists working for the United States federal government succeeded in producing nuclear weapons, making the United States the world's first nuclear power. Toward the end of World War II, after the end of World War II in Europe, the United States dropped atomic bombs on Hiroshima and Nagasaki, Japan. The Hiroshima and Nagasaki bombs were the second and third nuclear devices detonated and the only ones ever employed as weapons.
Japan surrendered soon after, on 2 September 1945, which ended World War II.<ref>Walker, John F, and Vatter, Harold G The Rise of Big Government in the United States. Page 63. M.E. Sharpe: May 1997. ISBN 0-7656-0067-6.</ref>
Cold War and civil rights
After World War II, the United States and the Soviet Union became superpowers in an era of ideological rivalry dubbed the Cold War. The United States promoted liberal democracy and capitalism, while the Soviet Union communism and a centrally planned economy. The result was a series of proxy wars, including the Korean War, the Vietnam War, the tense nuclear showdown of the Cuban Missile Crisis, and the Soviet war in Afghanistan.
The perception that the United States was losing the space race spurred government efforts to raise proficiency in mathematics and science in schools<ref>Rudolph, John L. Scientists in the Classroom: The Cold War Reconstruction of American Science Education. Page 1. Palgrave Macmillan: 3 May 2002. ISBN 0-312-29571-5.</ref> and led to President John F. Kennedy's call for the United States to land "a man on the moon" by the end of the 1960s, which was realized in 1969.<ref>Rudolph, John L. Scientists in the Classroom: The Cold War Reconstruction of American Science Education. Page 1. Palgrave Macmillan: 3 May 2002. ISBN 0-312-29571-5.</ref>
Meanwhile, American society experienced a period of sustained economic expansion. At the same time, discrimination across the United States, especially in the South, was increasingly challenged by a growing civil-rights movement headed by prominent African Americans such as Martin Luther King, Jr., which led to the abolition of the Jim Crow laws in the South.<ref>Klarman, Michael J. From Jim Crow to Civil Rights: The Supreme Court and the Struggle for Racial Equality. Page 552. Oxford University Press, USA: 4 May 2006. ISBN 0-19-531018-7.</ref>
After the fall of the Soviet Union in 1991, the United States continued to intervene in overseas military conflicts such as the Gulf War. It remains the world's only superpower.
September 11, 2001 and the War on Terrorism
On September 11 2001, 19 al-Qaeda operatives hijacked four commercial airplanes and flew two planes into the World Trade Center towers, one plane into The Pentagon; the fourth plane was brought down by passengers in Shanksville, Pennsylvania. After the 9/11 attacks, U.S. foreign policy then focused on the global threat of terrorism. In response, the United States government under President George W. Bush began a series of military and legal operations termed the War on Terror. The War on Terror began on October 7, 2001 when a U.S.-led coalition launched military operations in Afghanistan which led to the removal of the Taliban rule and the expulsion of the terrorist organization al-Qaeda and its leader Osama Bin Laden. The events of September 11 led to a preemptive policy against threats to U.S. security, known as the Bush Doctrine.
In the 2002 State of the Union address, President George W. Bush labeled North Korea, Iraq, and Iran "the axis of evil," and stated that these countries "constitute a grave threat to the security of the U.S. and its allies." Beginning later that year, the Bush administration began to press for regime change in Iraq. After many failed U.N. resolutions and Saddam Hussein rejecting demands to surrender, the United States and its allies invaded Iraq in March of 2003. The Bush administration justified its invasion with a charge that Iraq had stockpiled weapons of mass destruction, and was seeking nuclear weapons.<ref>http://www.whitehouse.gov/news/releases/2002/10/20021007-8.html</ref> After the invasion, only a limited number of non-nuclear stockpiles were found, and the Bush administration later admitted having acted on flawed intelligence. As of December 2006, Operation Iraqi Freedom remains an ongoing event.
Government and politics
Political system
The United States is the longest-surviving extant constitutional republic, with the oldest wholly written constitution in the world. Its government operates as a representative democracy through a congressional system under a set of powers specified by its Constitution. There are three levels of government: federal, state, and local. Officials at all three levels are either elected by voters in a secret ballot or appointed by other elected officials. Executive and legislative offices are decided by a plurality vote of citizens in their respective districts, with judicial and cabinet-level offices nominated by the Executive branch and approved by the Legislature. In some states, judicial posts are filled by popular election rather than executive appointment.
The federal government comprises three branches, which are designed to check and balance one another's powers:
- Legislative: The Congress, made up of the Senate and the House of Representatives, which makes federal law, declares war, approves treaties and has powers of impeachment.
- Executive: The President, who appoints, with Senate approval, the Cabinet and other officers, who administers and enforces federal law, can veto bills, and is Commander in Chief of the military.
- Judiciary: The Supreme Court and lower federal courts, whose judges are appointed by the President with Senate approval, that interpret laws and their validity under the Constitution, and can overturn laws they deem unconstitutional.
The United States Congress is a bicameral legislature. The House of Representatives has 435 members, each representing a congressional district for a two-year term. House seats are apportioned among the states according to population every tenth year. Each state is guaranteed at least one representative: currently, seven states have one each; California, the most populous state, has 53. Each state has two senators, elected at large to six-year terms; one third of Senate seats are up for election every second year.
The United States Constitution is the supreme legal document in the American system, and serves as a social contract between the people of the United States and their government. All laws and procedures of both state and federal governments are subject to review, and any law ruled to violate the Constitution by the judicial branch is overturned. The Constitution is a living document as it can be amended by a variety of methods, all of which require the approval of an overwhelming majority of the states. The Constitution has been amended 27 times, the last time in 1992.
The Constitution contains a dedication to "preserve liberty" with a "Bill of Rights" and other amendments, which guarantee freedom of speech, religion, and the press; the right to a fair trial; the right to keep and bear arms; universal suffrage; and property rights. However, the extent to which these rights are protected and universal in practice is heavily debated. The Constitution also guarantees to every State "a Republican Form of Government". However, the meaning of that guarantee has been only slightly explicated.<ref>http://caselaw.lp.findlaw.com/data/constitution/article04/</ref>
Since 2001, the President has been George W. Bush, a Republican. Following the 2006 mid-term elections, the Democratic Party holds a majority of seats in both the House and Senate for the first time since 1994, except for a Democratic plurality in the Senate in 2001–02,<ref>Secretary of the Senate. United States Senate Art & History: Party Division in the United States Senate, 1789—Present. Retrieved 21 June 2006.</ref>
Foreign relations and military
The United States has vast economic, political, and military influence on a global scale, which makes its foreign policy a subject of great interest and discussion around the world. Almost all countries have embassies in Washington, D.C., and consulates around the country. However, Cuba, Iran, North Korea, and Sudan do not have formal diplomatic relations with the United States.<ref>"Table 2 Aliens From Countries That Sponsor Terrorism Who Were Ordered Removed - 1 October 2000 through 31 December 2001". February 2003. U.S. Department of Justice. URL accessed May 30, 2006.</ref> The United States is a founding member of the United Nations (with a permanent seat on the Security Council), among many other international organizations.
The United States has a long-standing tradition of civilian control over military affairs. The Department of Defense administers the U.S. armed forces, which comprise the Army, the Navy, the Marine Corps, and the Air Force. The Coast Guard falls under the jurisdiction of the Department of Homeland Security in peacetime but is placed under the Department of the Navy in times of war.
The military of the United States comprises 1.4 million personnel on active duty,<ref>"Active Duty Military Personnel Strength Levels". 2002. Accessed 2 May 2006.</ref> along with several hundred thousand each in the Reserves and the National Guard. Service in the military is voluntary, though conscription may occur in times of war through the Selective Service System. The United States is considered to have the most powerful military in the world, partly because of the size of its defense budget; American defense expenditures in 2005 were estimated to be greater than the next 14 largest national military budgets combined,<ref>Anup Shah, High Military Expenditure in Some Places. Last updated 27 March, 2006. globalissues.org. Retrieved 30 June, 2006.</ref> even though the U.S. military budget is only about 4% of the country's gross domestic product.<ref>Military. 1 June 2006. CIA Factbook. Retrieved 3 June 2006.</ref><ref>Template:Cite web</ref> The U.S. military maintains over 700 bases and facilities. It also has bases on every continent except Antarctica.<ref>U.S. Department of Defense Base Structure Report, Fiscal Year 2005 Baseline. Retrieved 1 June 2006.</ref>
Administrative divisions
The conterminous, or contiguous, forty-eight states—all the states but Alaska and Hawaii—are also called the continental United States. Some include Alaska in the "continental" states, because, although it is separated from the "lower forty-eight" by Canada, it is part of the North American mainland. All of these terms commonly include the District of Columbia. Hawaii, the fiftieth state, occupies an archipelago in the Pacific Ocean.
The United States also holds several other territories, districts, and possessions, notably the federal district of the District of Columbia—which contains the nation's capital city, Washington—and several overseas insular areas, the most significant of which are American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and the United States Virgin Islands. Palmyra Atoll is the United States' only incorporated territory; but it is unorganized and uninhabited. The United States Minor Outlying Islands consist of uninhabited islands and atolls in the Pacific and Caribbean Sea. In addition, since 1898, the United States Navy has held an extensive naval base at Guantanamo Bay, Cuba.
In addition to the actual states and territories of the United States, there are also nations which are associated states of the U.S. The Federated States of Micronesia (since 1986), Palau (since 1994), and the Marshall Islands (since 1986) are associated with the United States under what is known as the Compact of Free Association, giving the states international sovereignty and ultimate control over their territory. However, the governments of those areas have agreed to allow the United States to provide defense and financial assistance.
Environment
The U.S. has over 17,000 identified native plant and tree species, including 5,000 just in California (which is home to the tallest, the most massive, and the oldest trees in the world).<ref>Morse, Larry E., et al, Native Vascular Plants, Our Living Resources, U.S. Department of the Interior, URL accessed 14 June 2006.</ref> With habitats ranging from tropical to arctic, the flora of the U.S. is the most diverse of any country; yet, thousands of non-native exotic species sometimes adversely affect indigenous plant and animal communities. Over 400 species of mammal, 700 species of bird, 500 species of reptile and amphibian, and 90,000 species of insect have been documented.<ref>National Biological Service, Our Living Resources, URL accessed 14 June 2006.</ref> Many plants and animals are very localized in their distribution, and some are in danger of extinction. The U.S. passed the Endangered Species Act in 1973 to protect native plant and animal species and their habitats.
Conservation has a long history in the U.S.; in 1872, the world's first National Park was established at Yellowstone. Another 57 national parks and hundreds of other federally managed parks and forests have since been designated.<ref>National Park Service, National Park Service Announces Addition of Two New Units, National Park Service News release (28 February 2006), URL accessed 13 June 2006.</ref> In some parts of the country, wilderness areas have been established to ensure long-term protection of pristine habitats. The U.S. Fish and Wildlife Service monitors endangered and threatened species and has set aside numerous areas for species and habitat preservation. Altogether, the U.S. government regulates 1,020,779 square miles (2,643,807 km²), which is 28.8% of the total land area of the U.S.<ref>Republican Study Committee, Federal Land and Buildings Ownership, (19 May 2005), URL accessed 13 June 2006.</ref> The bulk of this land is protected park and forestland, but some is leased for oil and gas exploration, mining, and cattle ranching.
Economy
General situation
The economic history of the United States is a story of economic growth that began with marginally successful colonial economies and progressed to the largest industrial economy in the world in the 20th and early 21st century.
The economic system of the United States can be described as a capitalist mixed economy, in which corporations, other private firms, and individuals make most microeconomic decisions, and governments prefer to take a smaller role in the domestic economy, although the combined role of all levels of government is relatively large, at 36% of the Gross Domestic Product (GDP). The U.S. has a small social safety net, and regulation of businesses is slightly less than the average of developed countries.<ref>Index of Economic Freedom 2006 by Heritage Foundation. URL accessed 13 May 2006.</ref> The United States' median household income in 2005 was $43,318.<ref name="US Census Bureau news release in regards to median income">Template:Cite web</ref>
Economic activity varies greatly across the country. For example, New York City is the center of the American financial, publishing, broadcasting, and advertising industries, while Los Angeles is the most important center for film and television production. The San Francisco Bay Area and the Pacific Northwest are major centers for technology. The Midwest is known for its reliance on manufacturing and heavy industry, with Detroit serving as the historic center of the American automotive industry, and Chicago serving as the business and financial capital of the region. The Southeast is a major area for agriculture, tourism, and the lumber industry, and, because of wages and costs below the national average, it continues to attract manufacturing.
The largest sector in the United States economy is services, which employs roughly three quarters of the work force.<ref>"Toward a Learning Economy" by Stephen A. Herzenberg, John A. Alic, and Howard Wial. 2006. Toward a Learning Economy. URL accessed 3 May 2006.</ref>
The economy is fueled by an abundance in natural resources such as coal, petroleum, and precious metals. However, the country still depends for much of its energy on foreign countries. In agriculture, the country is a top producer of corn, soy beans, rice, and wheat, with the Great Plains labeled as the "breadbasket of the world" for its tremendous agricultural output.<ref>Frazier, Ian. Great Plains. Page 9. 4 May 2001. Picador; 1st Picado edition. ISBN 0-312-27850-0</ref> The U.S. has a large tourist industry, ranking third in the world,<ref>The United States International Travel Industry- Key Facts About Inbound Tourism. 8 May 2000. ITA Office of Travel & Tourism Industries. URL accessed 3 May 2006.</ref> and is also a major exporter in goods such as airplanes, steel, weapons, and electronics. Canada accounts for 19% (more than any other nation) of the United States' foreign trade, followed by China, Mexico, and Japan.
While the per capita income of the United States is among the highest in the world, the wealth is comparatively concentrated. The per capita income is higher than the western European, but in 1990 income was distributed less equally.<ref>Income Distribution in Europe and the United States by A B Atkinson. September 1995. Nuffield College in Oxford. URL accessed June 3, 2006.</ref> Since 1975, the U.S. has a "two-tier" labor market in which virtually all the real income gains have gone to the top 20% of households, with most of those gains accruing to the very highest earners within that category.<ref>Economy. June 13, 2006. CIA World Factbook. URL accessed June 15, 2006.</ref> This polarization is the result of a relatively high level of economic freedom.<ref>[1]. September 2005. Fraser Institute. Accessed 18 July 2006.</ref>
The social mobility of U.S. residents relative to that of other countries is the subject of much debate. Some analysts have found that social mobility in the United States is low relative to other OECD states, specifically compared to Western Europe, Scandinavia and Canada.<ref>"Ever Higher Society, Ever Harder to Ascend: Whatever Happened to the Belief That Any American Could Get to the Top" The Economist. December 29, 2004. URL accessed 21 August 2006.</ref><ref>"Intergenerational Mobility in Europe and North America" Jo Blanden, Paul Gregg, and Stephen Malchin. April 2005. "URL accessed 21 August 2006."</ref><ref>"Do Poor Children Become Poor Adults? Lessons from a Cross Country Comparison of Generational Earnings Mobility" Miles Corak. March 2006. "URL accessed 21 August 2006."</ref> Low social mobility may stem in part from the U.S. educational system. Public education in the United States is funded mainly by local property taxes supplemented by state revenues. This frequently results in a wide difference in funding between poor districts or poor states and more affluent jurisdictions.<ref>"What Research Says About Unequal Funding for Schools in America" Bruce Biddle and David C. Berliner. Winter 2002. "URL accessed 21 August 2006."</ref><ref>"An Economic Perspective on Urban Education" William G. Gale, Meghan McNally, and Janet Rothenberg Pack. June 2003. "URL accessed 21 August 2006."</ref> In addition, the practice of legacy preference at elite universities gives preference to the children of alumni, who are often wealthy. This practice reduces available spaces for better-qualified lower income students.<ref>Alumni ties more important than grades Wall Street Journal</ref> Some analysts argue that relative social mobility in the U.S. peaked in the 1960s and declined rapidly beginning in the 1980s.<ref>New York Times. (Late Edition (East Coast)). New York, N.Y.: May 15, 2005. pg. 1.1</ref> Former Federal Reserve Board Chairman Alan Greenspan has also suggested that the growing income inequality and low class mobility of the U.S. economy may eventua