The United States of America—usually referred to as the United States, the U.S., or America—is a constitutional federal republic comprising fifty 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, and the state of Hawaii is an archipelago in the mid-Pacific. The country also possesses several territories, or insular areas, scattered around the Caribbean and Pacific.

At 3.79 million square miles (9.83 million km²) and with more than 300 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 nations, the product of large-scale immigration from many countries. The U.S. economy is the largest national economy in the world, with a nominal 2006 gross domestic product (GDP) of more than US$13 trillion (over 25% of the world total based on nominal GDP and almost 20% by purchasing power parity).

The nation was founded by thirteen colonies of Great Britain located along the Atlantic seaboard. On July 4, 1776, they jointly 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 nineteenth 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. The Spanish-American War and World War I confirmed the nation'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. In the post–Cold War era, the United States is the only remaining superpower—accounting for approximately 50% of global military spending—and a dominant economic, political, and cultural force in the world.

External linksEdit

Government

• Official U.S. Government Web Portal Gateway to governmental sites
• House Official site of the United States House of Representatives
• Library of Congress Official site of the Library of Congress
• Senate Official site of the United States Senate
• Supreme Court Official site of the Supreme Court of the United States
• White House Official site of the President of the United States

Overviews and Data

• InfoUSA Portal to U.S. Information Agency resources
• State Energy Profiles Economic, environmental, and energy data for each state
• State Fact Sheets Population, employment, income, and farm data from the U.S. Economic Research Service
• The 50 States of the U.S.A. Collected informational links for each state
• U.S. Census Housing and Economic Statistics Wide-ranging data from the U.S. Census Bureau
• United States CIA World Factbook entry
• United States Encyclopaedia Britannica entry

History

• Historical Documents Collected by the National Center for Public Policy Research
• U.S. National Mottos: History and Constitutionality Analysis by the Ontario Consultants on Religious Tolerance
• USA Collected links to historical data

Maps

• National Atlas of the United States Official maps from the U.S. Department of the Interior
• United States Satellite view at WikiMapia (not affiliated with Wikipedia/Wikimedia Foundation)

Other

• U.S. Citizenship and Immigration Services Official government site
• United States Travel guide and tourist information from Wikitravel (not affiliated with Wikipedia/Wikimedia Foundation)

Adapted from the Wikipedia article, "United States" http://en.wikipedia.org/wiki/United_States, used under the GNU Free Documentation License.