With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: The United States became the only country to have used nuclear weapons in warfare when they dropped atomic bombs on Japan during World War II.
text_B: The United States of America -LRB- USA -RRB- , commonly known as the United States -LRB- U.S. -RRB- or America , is a constitutional federal republic composed of 50 states , a federal district , five major self-governing territories , and various possessions .. territories. Territories of the United States. constitutional. constitutional. federal republic. federal republic. states. U.S. state. federal district. Washington, D.C.. self-governing territories. Territories of the United States. various possessions. United States Minor Outlying Islands. Forty-eight of the fifty states and the federal district are contiguous and located in North America between Canada and Mexico .. North. North America. states. U.S. state. federal district. Washington, D.C.. Forty-eight of the fifty states and the federal district. Contiguous United States. North America. North America. Canada. Canada. Mexico. Mexico. The state of Alaska is in the northwest corner of North America , bordered by Canada to the east and across the Bering Strait from Russia to the west .. North. North America. Alaska. Alaska. North America. North America. Canada. Canada. state of Alaska. Alaska. Bering Strait. Bering Strait. Russia. Russia. The state of Hawaii is an archipelago in the mid-Pacific Ocean .. Hawaii. Hawaii. state of Hawaii. Hawaii. archipelago. archipelago. Pacific Ocean. Pacific Ocean. The U.S. territories are scattered about the Pacific Ocean and the Caribbean Sea .. territories. Territories of the United States. Pacific Ocean. Pacific Ocean. Caribbean Sea. Caribbean Sea. Nine time zones are covered .. time zones. Time in the United States. The geography , climate and wildlife of the country are extremely diverse .. geography. geography of the United States. climate. climate of the United States. wildlife. Fauna of the United States. At 3.8 million square miles -LRB- 9.8 million km2 -RRB- and with over 324 million people , the United States is the world 's third - or fourth-largest country by total area , third-largest by land area , and the third-most populous .. third-most populous. List of countries and dependencies by population. It is one of the world 's most ethnically diverse and multicultural nations , and is home to the world 's largest immigrant population .. ethnically diverse. Race and ethnicity in the United States. multicultural. Multiculturalism. The capital is Washington , D.C. , and the largest city is New York City ; nine other major metropolitan areas -- each with at least 4.5 million inhabitants and the largest having more than 13 million people -- are Los Angeles , Chicago , Dallas , Houston , Philadelphia , Miami , Atlanta , Boston , and San Francisco .. New York City. New York City. metropolitan areas. List of Metropolitan Statistical Areas. Los Angeles. Greater Los Angeles Area. Chicago. Chicago metropolitan area. Dallas. Dallas–Fort Worth Metroplex. Houston. Greater Houston. Philadelphia. Delaware Valley. Miami. Miami metropolitan area. Atlanta. Atlanta metropolitan area. Boston. Greater Boston. San Francisco. San Francisco Bay Area. Paleo-Indians migrated from Asia to the North American mainland at least 15,000 years ago .. North. North America. American. Americans. Paleo-Indians migrated from Asia. Settlement of the Americas. European colonization began in the 16th century .. European colonization. European colonization of the Americas. The United States emerged from 13 British colonies along the East Coast .. 13 British colonies. Thirteen Colonies. East Coast. East Coast of the United States. colonies. Colony. Numerous disputes between Great Britain and the colonies following the Seven Years ' War led to the American Revolution , which began in 1775 .. American. Americans. Great Britain. Kingdom of Great Britain. American Revolution. American Revolution. colonies. Colony. On July 4 , 1776 , during the course of the American Revolutionary War , the colonies unanimously adopted the Declaration of Independence .. American. Americans. Independence. American Revolution. Declaration. United States Declaration of Independence. American Revolutionary War. American Revolutionary War. colonies. Colony. Declaration of Independence. United States Declaration of Independence. The war ended in 1783 with recognition of the independence of the United States by Great Britain , representing the first successful war of independence against a European power .. Great Britain. Kingdom of Great Britain. recognition of the independence of the United States. Treaty of Paris ( 1783 ). European power. colonial empire. The current constitution was adopted in 1788 , after the Articles of Confederation , adopted in 1781 , were felt to have provided inadequate federal powers .. Confederation. Articles of Confederation. current constitution. United States Constitution. Articles of Confederation. Articles of Confederation. The first ten amendments , collectively named the Bill of Rights , were ratified in 1791 and designed to guarantee many fundamental civil liberties .. Bill of Rights. United States Bill of Rights. fundamental civil liberties. Natural and legal rights. The United States embarked on a vigorous expansion across North America throughout the 19th century , displacing Native American tribes , acquiring new territories , and gradually admitting new states until it spanned the continent by 1848 .. North. North America. territories. Territories of the United States. Native. Native Americans in the United States. American. Americans. states. U.S. state. North America. North America. displacing Native American tribes. American Indian Wars. acquiring new territories. United States territorial acquisitions. admitting new states. List of U.S. states by date of admission to the Union. During the second half of the 19th century , the American Civil War led to the end of legal slavery in the country .. American. Americans. American Civil War. American Civil War. slavery in the country. slavery in the United States. By the end of that century , the United States extended into the Pacific Ocean , and its economy , driven in large part by the Industrial Revolution , began to soar .. Pacific Ocean. Pacific Ocean. Industrial Revolution. Industrial Revolution. The Spanish -- American War and confirmed the country 's status as a global military power .. Spanish. Spanish language. American. Americans. military. United States Armed Forces. The United States emerged from as a global superpower , the first country to develop nuclear weapons , the only country to use them in warfare , and a permanent member of the United Nations Security Council .. superpower. superpower. first country to develop nuclear weapons. Nuclear weapons and the United States. use them. Atomic bombings of Hiroshima and Nagasaki. permanent member. Permanent members of the United Nations Security Council. United Nations Security Council. United Nations Security Council. United Nations. United Nations. The end of the Cold War and the dissolution of the Soviet Union in 1991 left the United States as the world 's sole superpower .. superpower. superpower. Cold War. Cold War. dissolution of the Soviet Union. dissolution of the Soviet Union. sole superpower. hyperpower. The U.S. is a founding member of the United Nations , World Bank , International Monetary Fund , Organization of American States -LRB- OAS -RRB- , and other international organizations .. American. Americans. United Nations. United Nations. World Bank. World Bank. International Monetary Fund. International Monetary Fund. Organization of American States. Organization of American States. The United States is a highly developed country , with the world 's largest economy by nominal GDP and second-largest economy by PPP .. developed country. developed country. largest economy by nominal GDP. List of countries by GDP ( nominal ). second-largest economy by PPP. List of countries by GDP ( PPP ). Though its population is only 4.3 % of the world total , Americans hold nearly 40 % of the total wealth in the world .. The United States ranks among the highest in several measures of socioeconomic performance , including average wage , human development , per capita GDP , and productivity per person .. ranks among the highest. International rankings of the United States. average wage. List of countries by average wage. human development. Human Development Index. per capita GDP. List of countries by GDP ( nominal ) per capita. While the U.S. economy is considered post-industrial , characterized by the dominance of services and knowledge economy , the manufacturing sector remains the second-largest in the world .. U.S. economy. Economy of the United States. post-industrial. post-industrial society. services. Service ( economics ). knowledge economy. knowledge economy. Accounting for approximately a quarter of global GDP and a third of global military spending , the United States is the world 's foremost economic and military power .. global military spending. List of countries by military expenditures. military. United States Armed Forces. The United States is a prominent political and cultural force internationally , and a leader in scientific research and technological innovations .. cultural. Culture of the United States. scientific research and technological. Science and technology in the United States
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