The term America, for the lands of the western hemisphere, is believed to have been coined in 1507 after Amerigo Vespucci, an Italian explorer and cartographer. The full name of the country was first used officially in the Declaration of Independence, which was the "unanimous Declaration of the thirteen united States of America" adopted by the "Representatives of the united States of America" on July 4, 1776. The current name was finalized on November 15, 1777, when the Second Continental Congress adopted the Articles of Confederation, the first of which states, "The Stile of this Confederacy shall be 'The United States of America.'" The short form United States is also standard. Other common forms include the U.S., the USA, and America. Colloquial names include the U.S. of A. and the States. Columbia, a once popular name for the Americas and the United States, was derived from Christopher Columbus. It appears in the name "District of Columbia". 
The standard way to refer to a citizen of the United States is as an American. Though United States is the formal adjective, American and U.S. are the most common adjectives used to refer to the country ("American values," "U.S. forces"). American is rarely used in English to refer to people not connected to the United States.
The phrase "the United States" was originally treated as plural—e.g, "the United States are"—including in the Thirteenth Amendment to the Constitution, ratified in 1865. It became common to treat it as singular—e.g., "the United States is"—after the end of the Civil War. The singular form is now standard; the plural form is retained in the idiom "these United States.
The United States is situated almost entirely in the western hemisphere: the contiguous U.S. stretches from the Pacific Ocean on the west to the Atlantic Ocean on the east, with the Gulf of Mexico to the southeast; it is bordered by Canada on the north and Mexico on the south. Alaska is the largest state in area; separated from the contiguous U.S. by Canada, it touches the Pacific on the south and the Arctic Ocean on the north. Hawaii occupies an archipelago in the central Pacific, southwest of North America. After Russia and Canada, the U.S. is the world's third or fourth largest nation by total area, ranking just above or below China. The ranking varies depending on how two territories disputed by China and India are counted and how the total size of the U.S. is calculated: the CIA World Factbook gives 3,794,083 sq mi (9,826,630 km2. the United Nations Statistics Division gives 3,717,813 sq mi (9,629,091 km2. and the Encyclopedia Britannica gives 3,676,486 sq mi (9,522,055 km2.Including only land area, the U.S. is third in size behind Russia and China, just ahead of Canada. The U.S. also possesses several insular territories scattered around the West Indies (e.g., the commonwealth of Puerto Rico) and the Pacific (e.g., Guam).
The coastal plain of the Atlantic seaboard gives way further inland to deciduous forests and the rolling hills of the Piedmont. The Appalachian Mountains 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, at the western edge of the Great Plains, extend north to south across the country, reaching altitudes higher than 14,000 feet (4,300 m) in Colorado. Farther west are the rocky Great Basin and deserts such as the Mojave. The Sierra Nevada and Cascade mountain ranges run close to the Pacific coast. At 20,320 feet (6,194 m), Alaska's Mount McKinley is the country's tallest peak. 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 U.S., 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 southern tip of Florida is tropical, as is Hawaii. The Great Plains west of the 100th meridian are semi-arid. Much of the Western mountains are alpine. 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. Extreme weather is not uncommon—the states bordering the Gulf of Mexico are prone to hurricanes, and most of the world's tornadoes occur within the country, mainly in the Midwest's Tornado Alley.
The U.S. ecology is very diverse, with more than 17,000 native species of flora.and more than 400 mammal, 700 bird, 500 reptile and amphibian, and 90,000 insect species.The Endangered Species Act of 1973 protects threatened and endangered species and their habitats, which are monitored by the United States Fish and Wildlife Service. There are fifty-eight national parks and hundreds of other federally managed parks, forests, and wilderness areas.Altogether, the government regulates 28.8% of the country's land area. Most of this is protected, though some is leased for oil and gas drilling.mining, or cattle ranching.
The indigenous peoples of the U.S. mainland, including Alaska Natives, migrated from Asia. They began arriving at least 12,000 and as many as 40,000 years ago.Some, such as the pre-Columbian Mississippian culture, developed advanced agriculture, grand architecture, and state-level societies. In 1492, Genoese explorer Christopher Columbus, under contract to the Spanish crown, reached several Caribbean islands, making first contact with the indigenous people. Millions of indigenous Americans subsequently died from epidemics of Eurasian diseases.
On April 2, 1513, Spanish conquistador Juan Ponce de León landed on what he called "La Florida"—the first documented European arrival on what would become the U.S. mainland. Of Spain's settlements in the region, only St. Augustine, founded in 1565, remains. Later Spanish settlements in the present-day southwestern United States drew thousands through Mexico. French fur traders established outposts of New France around the Great Lakes; France eventually claimed much of the North American interior, down to the Gulf of Mexico. The first successful English settlements were the Virginia Colony in Jamestown in 1607 and the Pilgrims' Plymouth Colony in 1620. The 1628 chartering of the Massachusetts Bay Colony resulted in a wave of migration; by 1634, New England had been settled by some 10,000 Puritans. Between the late 1610s and the American Revolution, about 50,000 convicts were shipped to Britain's American colonies. Beginning in 1614, the Dutch settled along the lower Hudson River, including New Amsterdam on Manhattan Island.
In 1674, the Dutch ceded their American territory to England; the province of New Netherland was renamed New York. Many new immigrants, especially to the South, were indentured servants—some two-thirds of all Virginia immigrants between 1630 and 1680. By the turn of the century, African slaves were becoming the primary source of bonded labor. With the 1729 division of the Carolinas and the 1732 colonization of Georgia, the thirteen British colonies that would become the United States of America were established. All had local governments with elections open to most free men, with a growing devotion to the ancient rights of Englishmen and a sense of self-government stimulating support for republicanism. All legalized the African slave trade. With high birth rates, low death rates, and steady immigration, these colonies doubled in population every twenty-five years. The Christian revivalist movement of the 1730s and 1740s known as the Great Awakening fueled interest in both religion and religious liberty. In the French and Indian War, British forces seized Canada from the French, but the francophone population remained politically isolated from the southern colonies. By 1770, those thirteen colonies had an increasingly Anglicized population of three million, approximately half that of Britain. Though subject to British taxation, they had no representation in the Parliament of Great Britain.
Tensions between American colonials and the British during the revolutionary period of the 1760s and early 1770s led to the American Revolutionary War, fought from 1775 through 1781. On June 14, 1775, the Continental Congress, convening in Philadelphia, established a Continental Army under the command of George Washington. Proclaiming that "all men are created equal" and endowed with "certain unalienable Rights," the Congress adopted the Declaration of Independence, drafted largely by Thomas Jefferson, on July 4, 1776. That date is now celebrated annually as America's Independence Day. In 1777, the Articles of Confederation established a weak federal government that operated until 1789.
After the defeat of the British army by American forces who were assisted by the French, Great Britain recognized the independence of the United States and the states' sovereignty over American territory west to the Mississippi River. A constitutional convention was organized in 1787 by those wishing to establish a strong national government, with powers of taxation. The United States Constitution was ratified in 1788, and the new republic's first Senate, House of Representatives, and president—George Washington—took office in 1789. The Bill of Rights, forbidding federal restriction of personal freedoms and guaranteeing a range of legal protections, was adopted in 1791.
Attitudes toward slavery were shifting; a clause in the Constitution protected the African slave trade only until 1808. The Northern states abolished slavery between 1780 and 1804, leaving the slave states of the South as defenders of the "peculiar institution." The Second Great Awakening, beginning about 1800, made evangelicalism a force behind various social reform movements, including abolitionism.
Territorial acquisitions by date
Americans' eagerness to expand westward prompted a long series of Indian Wars and an Indian removal policy that stripped Native Americans (popularly known as "American Indians") of their land. The Louisiana Purchase of French-claimed territory under President Thomas Jefferson in 1803 almost doubled the nation's size. The War of 1812, declared against Britain over various grievances and fought to a draw, strengthened U.S. nationalism. A series of U.S. military incursions into Florida led Spain to cede it and other Gulf Coast territory in 1819. The U.S. annexed the Republic of Texas in 1845. The concept of Manifest Destiny was popularized during this time.The 1846 Oregon Treaty with Britain led to U.S. control of the present-day American Northwest. The U.S. victory in the Mexican-American War resulted in the 1848 cession of California and much of the present-day American Southwest. The California Gold Rush of 1848–49 further spurred western migration. New railways made relocation easier for settlers and increased conflicts with Native Americans. Over a half-century, up to 40 million American bison, or buffalo, were slaughtered for skins and meat and to ease the railways' spread. The loss of the buffalo, a primary resource for the plains Indians, was an existential blow to many native cultures.
Tensions between slave and free states mounted with arguments over the relationship between the state and federal governments, as well as violent conflicts over the spread of slavery into new states. Abraham Lincoln, candidate of the largely antislavery Republican Party, was elected president in 1860. Before he took office, seven slave states declared their secession—which the federal government maintained was illegal—and formed the Confederate States of America. With the Confederate attack upon Fort Sumter, the American Civil War began and four more slave states joined the Confederacy. Lincoln's Emancipation Proclamation committed the Union to ending slavery. Following the Union victory in 1865, three amendments to the U.S. Constitution ensured freedom for the nearly four million African Americans who had been slaves.made them citizens, and gave them voting rights. The war and its resolution led to a substantial increase in federal power.
After the war, the assassination of Lincoln radicalized Republican Reconstruction policies aimed at reintegrating and rebuilding the Southern states while ensuring the rights of the newly freed slaves. The resolution of the disputed 1876 presidential election by the Compromise of 1877 ended Reconstruction; Jim Crow laws soon disenfranchised many African Americans. In the North, urbanization and an unprecedented influx of immigrants hastened the country's industrialization. The wave of immigration, lasting until 1929, provided labor and transformed American culture. High tariff protections, national infrastructure building, and new banking regulations encouraged growth. The 1867 Alaska purchase from Russia completed the country's mainland expansion. The Wounded Knee massacre in 1890 was the last major armed conflict of the Indian Wars. In 1893, the indigenous monarchy of the Pacific Kingdom of Hawaii was overthrown in a coup led by American residents; the U.S. annexed the archipelago in 1898. Victory in the Spanish-American War the same year demonstrated that the U.S. was a major world power and led to the annexation of Puerto Rico, Guam, and the Philippines. The Philippines gained independence a half-century later; Puerto Rico and Guam remain U.S. territories.
At the outbreak of World War I in 1914, the United States remained neutral. Most Americans sympathized with the British and French, although many opposed intervention.In 1917, the U.S. joined the Allies, turning the tide against the Central Powers. After the war, the Senate did not ratify the Treaty of Versailles, which established the League of Nations. The country pursued a policy of unilateralism, verging on isolationism. In 1920, the women's rights movement won passage of a constitutional amendment granting women's suffrage. The prosperity of the Roaring Twenties ended with the Wall Street Crash of 1929 that triggered the Great Depression. After his election as president in 1932, Franklin D. Roosevelt responded with the New Deal, a range of policies increasing government intervention in the economy. The Dust Bowl of the mid-1930s impoverished many farming communities and spurred a new wave of western migration.
The U.S., effectively neutral during World War II's early stages after the Nazi invasion of Poland in September 1939, began supplying materiel to the Allies in March 1941 through the Lend-Lease program. On December 7, 1941, the U.S. joined the Allies against the Axis powers after a surprise attack on Pearl Harbor by Japan. World War II cost far more money than any other war in American history. but it boosted the economy by providing capital investment and jobs. Among the major combatants, the U.S. was the only nation to become richer—indeed, far richer—instead of poorer because of the war. Allied conferences at Bretton Woods and Yalta outlined a new system of international organizations that placed the U.S. and Soviet Union at the center of world affairs. As victory was achieved in Europe, a 1945 international conference held in San Francisco produced the United Nations Charter, which became active after the war.The U.S., having developed the first nuclear weapons, used them on the Japanese cities of Hiroshima and Nagasaki in August. Japan surrendered on September 2, ending the war.
The United States and Soviet Union jockeyed for power after World War II during the Cold War, dominating the military affairs of Europe through NATO and the Warsaw Pact. The U.S. promoted liberal democracy and capitalism, while the Soviet Union promoted communism and a centrally planned economy. Both supported dictatorships and engaged in proxy wars. American troops fought Communist Chinese forces in the Korean War of 1950–53. The House Un-American Activities Committee pursued a series of investigations into suspected leftist subversion, while Senator Joseph McCarthy became the figurehead of anticommunist sentiment.
The 1961 Soviet launch of the first manned spaceflight prompted President John F. Kennedy's call for the U.S. to be first to land "a man on the moon," achieved in 1969. Kennedy also faced a tense nuclear showdown with Soviet forces in Cuba. Meanwhile, the U.S. experienced sustained economic expansion. A growing civil rights movement, led by African Americans such as Martin Luther King, Jr., fought segregation and discrimination. Following Kennedy's assassination in 1963, the Civil Rights Act of 1964and Voting Rights Act of 1965 were passed under President Lyndon B. Johnson. Johnson and his successor, Richard Nixon, expanded a proxy war in Southeast Asia into the unsuccessful Vietnam War. A widespread countercultural movement grew, fueled by opposition to the war, the sexual revolution, and a new wave of feminism.
As a result of the Watergate scandal, in 1974 Nixon became the first U.S. president to resign, rather than be impeached on charges including obstruction of justice and abuse of power; he was succeeded by Vice President Gerald Ford. During the Jimmy Carter administration in the late 1970s, the U.S. economy experienced stagflation. The election of Ronald Reagan as president in 1980 marked a significant rightward shift in American politics, reflected in major changes in taxation and spending priorities. In the late 1980s and early 1990s, the Soviet Union collapsed, effectively ending the Cold War.
The leadership role taken by the United States and its allies in the UN–sanctioned Gulf War and the Yugoslav wars 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. In 1998, Clinton was impeached by the House on charges relating to a civil lawsuit and a sexual scandal, but was acquitted by the Senate and remained in office. The presidential election of 2000, one of the closest in U.S. history, was ultimately resolved by a U.S. Supreme Court decision—George W. Bush, son of George H. W. Bush, became president.
On September 11, 2001, al-Qaeda terrorists struck the World Trade Center in New York City and The Pentagon near Washington, D.C., killing nearly three thousand people. In response, President Bush launched the War on Terrorism. In late 2001, U.S. forces led a NATO invasion of Afghanistan, removing the Taliban government and al-Qaeda training camps. Taliban insurgents continue to fight a guerrilla war. In 2002, the Bush administration began to press for regime change in Iraq on controversial grounds. Lacking the support of NATO or an explicit UN mandate for military intervention, Bush organized a Coalition of the Willing; coalition forces preemptively invaded Iraq in 2003, removing President Saddam Hussein from power. Though most Americans now view the invasion as a mistake, the U.S.-led coalition maintains a presence in Iraq. The U.S. has been criticized for human rights violations in its pursuit of the War on Terrorism and the Iraq War.
The collapse of the U.S. housing bubble and the related subprime mortgage crisis led to a broader economic crisis in late summer/early fall 2008. In the upcoming 2008 presidential election, the Republican Party candidate, Senator John McCain of Arizona, a Vietnam War veteran and former prisoner of war, will face the Democratic Party candidate, Senator Barack Obama of Illinois, the first African American to head a major political party's presidential ticket.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, 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.
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.
The United States has operated under a two-party system for virtually all 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. A plurality of Americans identify as Democrats, yet significantly more Americans identify as conservative than liberal.
The incumbent president, Republican George W. Bush, is the 43rd U.S. president. All presidents to date have been white men. If Democrat Barack Obama wins the 2008 election, he will be the first African American president; if Republican John McCain wins, he will be the oldest man to take the office, and his running mate, Sarah Palin, will be the first female vice president. Following the 2006 midterm elections, the Democratic Party controls 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.
The United States is a federal union of fifty 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. The exceptions are Vermont, Texas, and Hawaii; each was an independent republic before joining the union. Early in the country's history, three states were created out of the territory of existing ones: Kentucky from Virginia; Tennessee from North Carolina; and Maine from Massachusetts. West Virginia broke away from Virginia during the American Civil War. The most recent state—Hawaii—achieved statehood on August 21, 1959. 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 U.S. also possesses five major territories with indigenous populations: Puerto Rico and 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.
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. 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, Cuba, Iran, North Korea, Bhutan, Sudan, and the Republic of China (Taiwan) do not have formal diplomatic relations with the United States.
The U.S. enjoys a special relationship with the United Kingdom and strong ties with Australia, New Zealand, Japan, Israel, 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 U.S. 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 1.38 million personnel on active duty. along with several hundred thousand each in the Reserves and the National Guard for a total of 2.3 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 U.S., the military is deployed to 770 bases and facilities, on every continent except Antarctica. The extent of this global military presence has prompted scholars to describe the U.S. as maintaining an "empire of bases.
Total U.S. military spending in 2006, over $528 billion, was 46% of global military spending and greater than the next fourteen largest national military expenditures combined. (In purchasing power parity terms, it was larger than the next six 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.The estimated cost of the Iraq War to the U.S. through 2016 is $2.267 trillion. As of September 22, 2008, the U.S. had suffered 4,169 military fatalities during the war and over 30,000 wounded.
The United States has a capitalist mixed economy, which is fueled by abundant natural resources, a well-developed infrastructure, and high productivity. According to the International Monetary Fund, the U.S. GDP of more than $13 trillion constitutes over 25.5% of the gross world product at market exchange rates and over 19% of the gross world product at purchasing power parity (PPP.The largest national GDP in the world, it was slightly less than the combined GDP of the European Union at PPP in 2006.The country ranks eighth in the world in nominal GDP per capita and fourth in GDP per capita at PPP.The U.S. is the largest importer of goods and third largest exporter, though exports per capita are relatively low. Canada, China, Mexico, Japan, and Germany are its top trading partners. The leading export commodity is electrical machinery, while vehicles constitute the leading import.
The private sector constitutes the bulk of the economy, with government activity accounting for 12.4% of GDP. The economy is postindustrial, with the service sector contributing 67.8% of GDP. The leading business field by gross business receipts is wholesale and retail trade; by net income it is finance and insurance.The U.S. remains an industrial power, with chemical products the leading manufacturing field. The U.S. is the third largest producer of oil in the world, as well as its largest importer.It is the world's number one producer of electrical and nuclear energy, as well as liquid natural gas, sulfur, phosphates, and salt. While agriculture accounts for just under 1% of GDP. the U.S. is the world's top producer of corn and soybeans.The leading cash crop is marijuana, despite federal laws making its cultivation and sale illegal. The New York Stock Exchange is the world's largest by dollar volume.Coca-Cola and McDonald's are the two most recognized brands in the world.
In 2005, 155 million persons were employed with earnings, of whom 80% had full-time jobs.The majority, 79%, were employed in the service sector. With about 15.5 million people, health care and social assistance is the leading field of employment. About 12% of workers are unionized, compared to 30% in Western Europe. The World Bank ranks the U.S. first in the ease of hiring and firing workers.Between 1973 and 2003, a year's work for the average American grew by 199 hours. Partly as a result, the U.S. maintains the highest labor productivity in the world. However, it no longer leads in productivity per hour as it did from the 1950s through the early 1990s; workers in Norway, France, Belgium, and Luxembourg are now more productive per hour.The U.S. ranks third in the World Bank's Ease of Doing Business Index.Compared to Europe, U.S. property and corporate income taxes are generally higher, while labor and, particularly, consumption taxes are lower.
According to the United States Census Bureau, the pretax median household income in 2007 was $50,233. The median ranged from $68,080 in Maryland to $36,338 in Mississippi.Using purchasing power parity exchange rates, the overall median is similar to the most affluent cluster of developed nations. After declining sharply during the middle of the 20th century, poverty rates have plateaued since the early 1970s, with 11–15% of Americans below the poverty line every year, and 58.5% spending at least one year in poverty between the ages of 25 and 75. In 2007, 37.3 million Americans lived in poverty.The U.S. welfare state is now among the most austere in the developed world, reducing both relative poverty and absolute poverty by considerably less than the mean for rich nations. While the American welfare state does well in reducing poverty among the elderly. the young are given relatively short shrift. A 2007 UNICEF study of children's well-being in twenty-one industrialized nations ranked the U.S. next to last.
Despite strong increases in productivity, low unemployment, and low inflation, income gains since 1980 have been slower than in previous decades, less widely shared, and accompanied by increased economic insecurity. Between 1947 and 1979, real median income rose by over 80% for all classes, with the incomes of poor Americans rising faster than those of the rich. Median household income has increased for all classes since 1980. largely owing to more dual-earner households, the closing of the gender gap, and longer work hours, but growth has been slower and strongly tilted toward the very top (see graph.Consequently, the share of income of the top 1% has doubled since 1979.leaving the U.S. with the greatest income inequality among developed nations. Wealth, like income, is highly concentrated: The richest 10% of the adult population possesses 69.8% of the country's household wealth, the second-highest share among developed nations. The top 1% possesses 33.4% of net wealth.
The United States has been a leader in scientific research and technological innovation since the late 19th century. In 1876, Alexander Graham Bell was awarded the first U.S. patent for the telephone. Thomas Edison's laboratory developed the phonograph, the first long-lasting light bulb, and the first viable movie camera. In the early 20th century, the automobile companies of Ransom E. Olds and Henry Ford pioneered the assembly line. The Wright brothers, in 1903, made the first sustained and controlled heavier-than-air powered flight.The rise of Nazism in the 1930s led many European scientists, including Albert Einstein and Enrico Fermi, to immigrate to the U.S. During World War II, the Manhattan Project developed nuclear weapons, ushering in the Atomic Age. The Space Race produced rapid advances in rocketry, materials science, and computers. The U.S. largely developed the ARPANET and its successor, the Internet. Today, the bulk of research and development funding, 64%, comes from the private sector.The U.S. leads the world in scientific research papers and impact . Americans possess high levels of technological consumer goods. and almost half of U.S. households have broadband Internet service. The country is the primary developer and grower of genetically modified food; more than half of the world's land planted with biotech crops is in the U.S.As of 2003, there were 759 automobiles per 1,000 Americans, compared to 472 per 1,000 inhabitants of the European Union the following year.About 40% of personal vehicles are vans, SUVs, or light trucks. The average American adult (accounting for all drivers and nondrivers) spends 55 minutes driving every day, travelling 29 miles (47 km. The U.S. intercity passenger rail system is relatively weak. Only 9% of total U.S. work trips use mass transit, compared to 38.8% in Europe. Bicycle usage is minimal, well below European levels.The civil airline industry is entirely privatized, while most major airports are publicly owned. The five largest airlines in the world by passengers carried are American; American Airlines is number one.Of the world's thirty busiest passenger airports, sixteen are in the U.S., including the busiest, Hartsfield-Jackson Atlanta International Airport (ATL.The United States energy market is 29 petawatts hours per year. Energy consumption per capita is 7.8 tons of oil equivalent per year, compared to Germany's 4.2 tons and Canada's 8.3 tons. In 2005, 40% of this energy came from petroleum, 23% from coal, and 22% from natural gas. The remainder was supplied by nuclear power and renewable energy sources. The U.S. is the world's largest consumer of petroleum.For decades, nuclear power has played a limited role relative to many other developed countries. Recently, applications for new nuclear plants have been filed.
The United States population is projected by the U.S. Census Bureau to be 305,395,000. including an estimated 11.2 million illegal immigrants.The U.S. is the third most populous nation in the world, after China and India. Its population growth rate is 0.89%.compared to the European Union's 0.16%.The birth rate of 14.16 per 1,000, 30% below the world average, is higher than any European country's except Albania and Ireland. In fiscal year 2007, 1.05 million immigrants were granted legal residence. Mexico has been the leading source of new residents for over two decades; since 1998, China, India, and the Philippines have been in the top four sending countries every year.The U.S. is the only industrialized nation in which large population increases are projected.
The U.S. has a very diverse population—thirty-one ancestry groups have more than a million members. White Americans are the largest racial group, with German Americans, Irish Americans, and English Americans constituting three of the country's four largest ancestry groups.African Americans are the nation's second largest racial minority group, after Hispanics/Latinos, and third largest ancestry group. Asian Americans are the country's second largest racial minority; the two largest Asian American ancestry groups are Chinese and Filipino. In 2007, the U.S. population included an estimated 4.5 million people with some American Indian or Alaskan native ancestry (2.9 million exclusively of such ancestry) and over 1 million with some native Hawaiian or Pacific island ancestry (0.5 million exclusively.
The population growth of Hispanic and Latino Americans (the terms are officially interchangeable) is a major demographic trend. The 45.4 million Americans of Hispanic descent are collated into a distinct "ethnicity" by the Census Bureau; 64% of Hispanic Americans are of Mexican descent.Between 2000 and 2007, the country's Hispanic population increased 27% while the non-Hispanic population rose just 3.6%.Much of this growth is from immigration; as of 2006, 12.1% of the U.S. population was foreign-born, with 54% of that figure born in Latin America.Fertility is also a factor; the average Hispanic woman gives birth to three children in her lifetime. The comparable fertility rate is 2.2 for non-Hispanic black women and 1.8 for non-Hispanic white women (below the replacement rate of 2.1).
Minorities (as defined by the Census Bureau, all those beside non-Hispanic, non-multiracial whites) constitute 34% of the population; they are projected to be the majority by 2042.However, White Americans overall (non-Hispanic Whites together with White Hispanics) are projected to remain the racial majority at 73.1% (or 303 million out of 420 million) in 2050.
About 79% of Americans live in urban areas (as defined by the Census Bureau, such areas include the suburbs); about half of those reside in cities with populations over 50,000.In 2006, 254 incorporated places had populations over 100,000, nine cities had more than 1 million residents, and four global cities had over 2 million (New York City, Los Angeles, Chicago, and Houston).There are fifty metropolitan areas with populations greater than 1 million. Of the fifty fastest-growing metro areas, twenty-three are in the West and twenty-five in the South. The metro areas of Atlanta, Dallas, Houston, Phoenix, and Riverside all grew by more than three-quarters of a million people between 2000 and 2006.
