United States

== History ==
{{Main|History of the United States}}
{{For outline|Outline of United States history}}

=== Indigenous peoples ===
{{Further|Native Americans in the United States|Pre-Columbian era}}
[[File:Extreme_Makeover,_Mesa_Verde_Edition_-_panoramio.jpg|left|thumb|[[Cliff Palace]], built by [[Ancestral Puebloans]] in present-day [[Montezuma County, Colorado]], between {{Circa|1200 and 1275}}<ref>[https://coloradoencyclopedia.org/article/cliff-palace "Cliff Palace"] at Colorado Encyclopedia. Retrieved January 31, 2024</ref>]]
The [[Paleo-Indians|first inhabitants of North America]] migrated from [[Siberia]] across the [[Bering land bridge]] at least 12,000 years ago;{{sfn|Erlandson|Rick|Vellanoweth|2008|p=19}}{{sfn|Savage|2011|page=55}} the [[Clovis culture]], which appeared around 11,000 BC, is believed to be the first widespread culture in the Americas.{{sfn|Waters|Stafford|2007|pages=1122–1126}}{{sfn|Flannery|2015|pages=173–185}} Over time, indigenous North American cultures grew increasingly sophisticated, and some, such as the [[Mississippian culture]], developed [[Eastern Agricultural Complex|agriculture]], [[Southeastern Ceremonial Complex|architecture]], and complex societies.{{sfn|Lockard|2010|page=315}} Indigenous peoples and cultures such as the [[Algonquian peoples]],<ref>Smithsonian Institution—Handbook of North American Indians series: ''Handbook of North American Indians,'' Volume 15—Northeast. Bruce G. Trigger (volume editor). Washington, DC: Smithsonian Institution. 1978 References to Indian burning for the Eastern Algonquians, Virginia Algonquians, Northern Iroquois, Huron, Mahican, and Delaware Tribes and peoples.</ref> [[Ancestral Puebloans]],{{sfn|Fagan|2016|page=390}} and the [[Iroquois]] developed across the present-day United States.<ref name="Dean Snow2">{{cite book |last=Snow |first=Dean R. |url=https://books.google.com/books?id=P7e82KQoX6IC&q=iroquois+basque&pg=PA1 |title=The Iroquois |publisher=Blackwell Publishers, Ltd. |year=1994 |isbn=978-1-55786-938-8 |access-date=July 16, 2010}}</ref> [[Population history of the Indigenous peoples of the Americas|Native population estimates]] of what is now the United States before the arrival of European immigrants range from around 500,000{{sfn|Thornton|1998|page=34}}{{sfn|Perdue|Green|2005|page=40}} to nearly 10 million.{{sfn|Perdue|Green|2005|page=40}}{{sfn|Haines|Haines|Steckel|2000|page=12}}

=== European colonization ===
{{Main|Colonial history of the United States}}
{{See also|European colonization of the Americas}}
[[File:Nouvelle-France map-en.svg|thumb|The 1750 [[Colonial history of the United States|colonial]] possessions of [[British colonization of the Americas|Britain]] (in pink and purple), [[New France|France]] (in blue), and [[Kingdom of Spain|Spain]] (in orange) in present-day [[Canada]] and the United States]]

[[Christopher Columbus]] began exploring the [[Caribbean]] in 1492, leading to [[Spanish Empire|Spanish]] settlements in present-day Puerto Rico, Florida, and [[New Mexico]].<ref>{{cite journal |last1=Davis |first1=Frederick T. |year=1932 |title=The Record of Ponce de Leon's Discovery of Florida, 1513 |url=http://palmm.digital.flvc.org/islandora/object/ucf%3A21231 |journal=The QUARTERLY Periodical of THE FLORIDA HISTORICAL SOCIETY |volume=XI |issue=1 |pages=5–6}}</ref><ref>{{cite book |author=Florida Center for Instructional Technology |url=https://fcit.usf.edu/florida/lessons/menendz/menendz1.htm |title=A Short History of Florida |date=2002 |publisher=University of South Florida |chapter=Pedro Menendez de Aviles Claims Florida for Spain}}<!--Online textbook for Florida public schools.--></ref><ref>{{cite web |date=February 28, 2015 |title=Not So Fast, Jamestown: St. Augustine Was Here First |url=https://www.npr.org/2015/02/28/389682893/not-so-fast-jamestown-st-augustine-was-here-first |access-date=March 5, 2021 |publisher=NPR |language=en}}</ref> [[Kingdom of France|France]] established [[New France|its own settlements]] along the [[Mississippi River]] and [[Gulf of Mexico]].<ref name="Petto20072">{{cite book |author=Petto |first=Christine Marie |url=https://books.google.com/books?id=9ZiaAAAAQBAJ&pg=PA125 |title=When France Was King of Cartography: The Patronage and Production of Maps in Early Modern France |publisher=Lexington Books |year=2007 |isbn=978-0-7391-6247-7 |page=125}}</ref> [[British colonization of the Americas|British colonization]] of the [[East Coast of the United States|East Coast]] began with the [[Colony of Virginia|Virginia Colony]] (1607) and [[Plymouth Colony]] (1620).<ref name="Jr.Selby20182">{{cite book |last1=Seelye |first1=James E. Jr. |url=https://books.google.com/books?id=YgVnDwAAQBAJ&pg=PA344 |title=Shaping North America: From Exploration to the American Revolution &#91;3 volumes&#93; |last2=Selby |first2=Shawn |publisher=ABC-CLIO |year=2018 |isbn=978-1-4408-3669-5 |page=344}}</ref><ref name="BellahSullivan20062">{{cite book |last1=Bellah |first1=Robert Neelly |url=https://books.google.com/books?id=5DQHmykT6u4C&pg=PA220 |title=Habits of the Heart: Individualism and Commitment in American Life |last2=Madsen |first2=Richard |last3=Sullivan |first3=William M. |last4=Swidler |first4=Ann |last5=Tipton |first5=Steven M. |publisher=University of California Press |year=1985 |isbn=978-0-520-05388-5 |page=220 |ol=7708974M}}</ref> The [[Mayflower Compact]] and the [[Fundamental Orders of Connecticut]] established precedents for representative [[self-governance]] and [[constitutionalism]] that would develop throughout the American colonies.<ref name="Remini2–32">{{Harvard citation no brackets|Remini|2007|pp=2–3}}</ref><ref name="Johnson26–302">{{Harvard citation no brackets|Johnson|1997|pp=26–30}}</ref> While European settlers in what is now the United States experienced conflicts with Native Americans, they also engaged in trade, exchanging European tools for food and animal pelts.<ref>[[United States#Ripper2008|Ripper, 2008]] p. 6</ref>{{efn|From the late 15th century, the [[Columbian exchange]] had been catastrophic for native populations throughout the Americas. It is estimated [[Virgin soil epidemic|that up to 95 percent of the indigenous populations]], especially in the Caribbean, [[Native American disease and epidemics|perished from infectious diseases during the years following European colonization]];<ref>{{Cite journal |last1=Ehrenpreis |first1=Jamie E. |last2=Ehrenpreis |first2=Eli D. |date=April 2022 |title=A Historical Perspective of Healthcare Disparity and Infectious Disease in the Native American Population |journal=The American Journal of the Medical Sciences |volume=363 |issue=4 |pages=288–294 |doi=10.1016/j.amjms.2022.01.005 |issn=0002-9629 |pmc=8785365 |pmid=35085528}}</ref> remaining populations were often displaced by European expansion.{{sfn|Joseph|2016|page=590}}<ref>[[United States#Stannard|Stannard, 1993]] p. [[iarchive:americanholocaus00stan|xii]]</ref>}} Relations ranged from close cooperation to warfare and massacres. The colonial authorities often pursued policies that forced Native Americans to adopt European lifestyles, including conversion to Christianity.<ref>[[United States#Ripper2008|Ripper, 2008]] p. 5</ref><ref>[[United States#Calloway1998|Calloway, 1998]], p. 55</ref> Along the eastern seaboard, settlers [[Slavery in the colonial history of the United States|trafficked African slaves]] through the [[Atlantic slave trade]].<ref>{{Cite book |last=Thomas |first=Hugh |url=https://archive.org/details/slavetradestoryo00thom/page/516 |title=The Slave Trade: The Story of the Atlantic Slave Trade: 1440{{ndash}}1870 |publisher=Simon and Schuster |year=1997 |isbn=0-684-83565-7 |pages=[https://archive.org/details/slavetradestoryo00thom/page/516 516] |url-access=registration}}</ref>

The original [[Thirteen Colonies]]{{efn|[[Province of New Hampshire|New Hampshire]], [[Province of Massachusetts Bay|Massachusetts]], [[Connecticut Colony|Connecticut]], [[Colony of Rhode Island and Providence Plantations|Rhode Island]], [[Province of New York|New York]], [[Province of New Jersey|New Jersey]], [[Province of Pennsylvania|Pennsylvania]], [[Delaware Colony|Delaware]], [[Province of Maryland|Maryland]], [[Colony of Virginia|Virginia]], [[Province of North Carolina|North Carolina]], [[Province of South Carolina|South Carolina]], and [[Province of Georgia|Georgia]]}} that would later found the United States were administered by [[British Empire|Great Britain]],<ref name="BilhartzElliott20072">{{cite book |author1=Bilhartz, Terry D. |url=https://archive.org/details/currentsinameric0000bilh |title=Currents in American History: A Brief History of the United States |author2=Elliott, Alan C. |publisher=M.E. Sharpe |year=2007 |isbn=978-0-7656-1817-7 |url-access=registration}}</ref> and had [[Colonial government in the Thirteen Colonies|local governments]] with elections open to most white male property owners.<ref name="Wood19982">{{cite book |author=Wood |first=Gordon S. |url=https://archive.org/details/creationofameric0000wood_r7v4 |title=The Creation of the American Republic, 1776–1787 |publisher=UNC Press Books |year=1998 |isbn=978-0-8078-4723-7 |page=263}}</ref><ref>{{cite journal |last=Ratcliffe |first=Donald |year=2013 |title=The Right to Vote and the Rise of Democracy, 1787–1828 |journal=Journal of the Early Republic |volume=33 |issue=2 |page=220 |doi=10.1353/jer.2013.0033 |s2cid=145135025}}</ref> The colonial population grew rapidly, eclipsing Native American populations;<ref>[[United States#Walton|Walton, 2009]], pp. 38–39</ref> by the 1770s, the natural increase of the population was such that only a small minority of Americans had been born overseas.<ref>[[United States#Walton|Walton, 2009]], p. 35</ref> The colonies' distance from Britain allowed for the development of self-governance,<ref>{{cite book |author=Otis |first=James |url=https://archive.org/details/cihm_52678 |title=The Rights of the British Colonies Asserted and Proved |year=1763 |isbn=978-0-665-52678-7}}</ref> and the [[First Great Awakening]], a series of [[Christian revival]]s, fueled colonial interest in [[Freedom of religion|religious liberty]].<ref>{{cite book |last1=Foner |first1=Eric |url=https://archive.org/details/storyofamericanf00fone |title=The Story of American Freedom |date=1998 |publisher=W.W. Norton |isbn=978-0-393-04665-6 |edition=1st |pages=[https://archive.org/details/storyofamericanf00fone/page/4 4]–5 |quote=story of American freedom. |url-access=registration}}</ref>

===American Revolution and Revolutionary War===
{{Main|American Revolution|American Revolutionary War}}
{{Further|History of the United States (1776–1789)|History of the United States (1789–1815)}}
[[File:Declaration_independence.jpg|alt=See caption|thumb|''[[Declaration of Independence (Trumbull)|Declaration of Independence]]'', a portrait by [[John Trumbull]] depicting the [[Committee of Five]] presenting the draft of the [[United States Declaration of Independence|Declaration]] to the [[Second Continental Congress|Continental Congress]] on June 28, 1776, in [[Philadelphia]]]]
After winning the [[French and Indian War]], Britain began to assert greater control over local colonial affairs, creating [[American Revolution|colonial political resistance]]; one of the primary colonial grievances was a denial of their [[Rights of Englishmen|rights as Englishmen]], particularly the right to [[No taxation without representation|representation in the British government that taxed them]]. In 1774, the [[First Continental Congress]] met in [[Philadelphia]], and passed a [[Continental Association|colonial boycott of British goods]] that proved effective. The British attempt to then disarm the colonists resulted in the 1775 [[Battles of Lexington and Concord]], igniting the [[American Revolutionary War]]. At the [[Second Continental Congress]], the colonies appointed [[George Washington]] commander-in-chief of the [[Continental Army]] and created [[Committee of Five|a committee]] led by [[Thomas Jefferson]] to write the [[United States Declaration of Independence|Declaration of Independence]], adopted on July 4, 1776.<ref name="YoungNash20112">{{cite book |author1=Fabian Young, Alfred |url=https://books.google.com/books?id=QEzaLJ4u_MEC&pg=PA4 |title=Revolutionary Founders: Rebels, Radicals, and Reformers in the Making of the Nation |author2=Nash, Gary B. |author3=Raphael, Ray |publisher=Random House Digital |year=2011 |isbn=978-0-307-27110-5 |pages=4–7}}</ref> The political values of the American Revolution included [[liberty]]'','' [[Natural rights and legal rights|inalienable individual rights]]; and the [[Popular sovereignty|sovereignty of the people]];<ref>Yick Wo vs. Hopkins, 118 U.S. 356, 370</ref> supporting [[Republicanism in the United States|republicanism]] and rejecting [[monarchy]], [[aristocracy]], and hereditary political power; virtue and faithfulness in the performance of civic duties; and vilification of [[corruption]].<ref>Richard Buel, ''Securing the Revolution: Ideology in American Politics, 1789–1815'' (1972)</ref> The [[Founding Fathers of the United States]], which included George Washington, [[Benjamin Franklin]], [[Alexander Hamilton]], [[Thomas Jefferson]], [[John Jay]], [[James Madison]], [[Thomas Paine]], and [[John Adams]], were inspired by [[Greco-Roman world|Greco-Roman]], [[Renaissance]], and [[Age of Enlightenment]] philosophies and ideas.<ref>Becker et al (2002), ch 1</ref><ref name="SEoP-2006">{{cite web |date=19 June 2006 |title=Republicanism |url=https://plato.stanford.edu/entries/republicanism/ |access-date=20 September 2022 |website=Stanford Encyclopedia of Philosophy}}</ref>

After the British surrender at the [[siege of Yorktown]] in 1781, American sovereignty was internationally recognized by the [[Treaty of Paris (1783)]], through which the U.S. gained territory stretching west to the Mississippi River, north to present-day Canada, and south to [[Spanish Florida]].<ref>{{cite web |editor-last=Miller |editor-first=Hunter |title=British-American Diplomacy: The Paris Peace Treaty of September 30, 1783 |url=http://avalon.law.yale.edu/18th_century/paris.asp |publisher=The Avalon Project at Yale Law School}}</ref> Ratified in 1781, the [[Articles of Confederation]] established a decentralized government that operated until 1789.<ref name="YoungNash20112" /> The [[Northwest Ordinance]] (1787) established the precedent by which the country's territory would expand with the [[Admission to the Union|admission of new states]], rather than the expansion of existing states.<ref>Shōsuke Satō, ''[https://books.google.com/books?id=PY0VAAAAYAAJ History of the land question in the United States]'', Johns Hopkins University, (1886), p. 352</ref> The [[Constitution of the United States|U.S. Constitution]] was drafted at the 1787 [[Constitutional Convention (United States)|Constitutional Convention]] to overcome the limitations of the Articles; it went into effect in 1789, creating a federation administered by [[Separation of powers|three branches]] on the principle of [[checks and balances]].{{sfn|Foner|2020|p=524}} Washington [[1788–89 United States presidential election|was elected]] the country's first president under the Constitution, and the [[United States Bill of Rights|Bill of Rights]] was adopted in 1791 to allay concerns by skeptics of the more centralized government;{{sfn|OpenStax|2014|loc=§ [https://openstax.org/books/us-history/pages/8-1-competing-visions-federalists-and-democratic-republicans 8.1]}}{{sfn|Foner|2020|pp=538-540}} [[George Washington's resignation as commander-in-chief#Legacy|his resignations first as commander-in-chief]] after the Revolution and later as president set a precedent followed by [[John Adams]], establishing the [[Peaceful transition of power|peaceful transfer of power]] between rival parties.<ref name="BoyerJr.20072">[[United States#Boyer|Boyer, 2007]], pp. 192–193</ref>{{sfn|OpenStax|2014|loc=§ [https://openstax.org/books/us-history/pages/8-1-competing-visions-federalists-and-democratic-republicans 8.3]}}

===Westward expansion===
{{Further||History of the United States (1815–1849)|Territorial evolution of the United States}}
[[File:US Slave Free 1789-1861.gif|thumb|Animation showing the free/slave status of U.S. states and territories expansion, 1789–1861]]
In the late 18th century, American settlers began to [[Territorial evolution of the United States|expand westward]], some with a sense of [[manifest destiny]].<ref name="MD20072">{{Cite book |last1=Carlisle |first1=Rodney P. |url=https://www.worldcat.org/oclc/659807062 |title=Manifest destiny and the expansion of America |last2=Golson |first2=J. Geoffrey |date=2007 |publisher=ABC-CLIO |isbn=978-1-85109-834-7 |series=Turning Points in History Series |location=Santa Barbara, Calif. |page=238 |oclc=659807062}}</ref> The [[Louisiana Purchase]] (1803) from France nearly doubled the territory of the United States.<ref>{{cite web |title=Louisiana Purchase |url=https://www.nps.gov/jeff/historyculture/upload/louisiana_purchase.pdf |access-date=March 1, 2011 |publisher=National Park Service}}</ref> [[Origins of the War of 1812|Lingering issues with Britain remained]], leading to the [[War of 1812]], which was fought to a draw.<ref name="Wait19992">{{cite book |last=Wait |first=Eugene M. |url=https://books.google.com/books?id=puuQ30N0EsIC&pg=PA78 |title=America and the War of 1812 |publisher=Nova Publishers |year=1999 |isbn=978-1-56072-644-9 |page=78}}</ref> [[Adams–Onís Treaty|Spain ceded Florida]] and its Gulf Coast territory in 1819.<ref name="KloseJones19942">{{cite book |author1=Klose, Nelson |url=https://archive.org/details/unitedstateshist00klos_0/page/150 |title=United States History to 1877 |author2=Jones, Robert F. |publisher=Barron's Educational Series |year=1994 |isbn=978-0-8120-1834-9 |page=[https://archive.org/details/unitedstateshist00klos_0/page/150 150]}}</ref> The [[Missouri Compromise]] attempted to balance desires of northern states to prevent expansion of slavery in the country with those of southern states to expand it, admitting [[Missouri]] as a [[Slave states and free states|slave state]] and [[Maine#Statehood|Maine]] as a free state and declared a policy of prohibiting slavery in the remaining Louisiana Purchase lands north of the [[parallel 36°30′ north|36°30′ parallel]].<ref>{{Cite journal|last=Hammond|first=John Craig|date=March 2019|title=President, Planter, Politician: James Monroe, the Missouri Crisis, and the Politics of Slavery|journal=Journal of American History|volume=105|issue=4|pages=843–867|doi=10.1093/jahist/jaz002}}</ref> As Americans expanded further into land inhabited by Native Americans, the federal government often applied [[Federal Indian Policy|policies]] of [[Indian removal]] or [[Cultural assimilation of Native Americans|assimilation]].<ref>{{Cite book |last=Frymer |first=Paul |url=https://www.worldcat.org/oclc/981954623 |title=Building an American empire : the era of territorial and political expansion |date=2017 |publisher=[[Princeton University Press]] |isbn=978-1-4008-8535-0 |location=Princeton, New Jersey |oclc=981954623}}</ref><ref>{{Cite book |last=Calloway |first=Colin G. |url=https://www.worldcat.org/oclc/1035393060 |title=First peoples : a documentary survey of American Indian history |date=2019 |publisher=Bedford/St. Martin's, Macmillan Learning |isbn=978-1-319-10491-7 |edition=6th |location=Boston |oclc=1035393060}}</ref> The infamous [[Trail of Tears]] (1830&ndash;1850) was a U.S.
government policy that forcibly removed and displaced most Native Americans living east of the [[Mississippi River]] to lands far to the west. These and earlier organized displacements prompted a long series of [[American Indian Wars]] west of the Mississippi.<ref>{{Cite book |last=Michno |first=Gregory |title=Encyclopedia of Indian Wars: Western Battles and Skirmishes, 1850–1890 |date=2003 |publisher=Mountain Press Publishing |isbn=978-0-87842-468-9}}</ref><ref name="BillingtonRidge2001j2">{{cite book |author1=Billington, Ray Allen |url=https://archive.org/details/westwardexpansio00bill/page/22 |title=Westward Expansion: A History of the American Frontier |author2=Ridge, Martin |publisher=UNM Press |year=2001 |isbn=978-0-8263-1981-4 |page=[https://archive.org/details/westwardexpansio00bill/page/22 22] |author-link2=Martin Ridge (historian)}}</ref> The [[Republic of Texas]] was [[Texas annexation|annexed]] in 1845,<ref name="Morrison19992">{{cite book |author=Morrison, Michael A. |url=https://books.google.com/books?id=YTaxzMlkVEMC&pg=PA13 |title=Slavery and the American West: The Eclipse of Manifest Destiny and the Coming of the Civil War |date=April 28, 1997 |publisher=University of North Carolina Press |isbn=978-0-8078-4796-1 |pages=13–21}}</ref> and the 1846 [[Oregon Treaty]] led to U.S. control of the present-day [[Northwestern United States|American Northwest]].<ref name="Kemp20102">{{cite book |author=Kemp, Roger L. |url=https://books.google.com/books?id=JHawgM-WnlUC&pg=PA180 |title=Documents of American Democracy: A Collection of Essential Works |publisher=McFarland |year=2010 |isbn=978-0-7864-4210-2 |page=180 |access-date=October 25, 2015}}</ref> Victory in the [[Mexican–American War]] resulted in the 1848 [[Mexican Cession]] of California and much of the present-day [[Southwestern United States|American Southwest]].<ref name="MD20072" /><ref name="McIlwraithMuller20012">{{cite book |author1=McIlwraith, Thomas F. |url=https://archive.org/details/northamericahist00mcil/page/61 |title=North America: The Historical Geography of a Changing Continent |author2=Muller, Edward K. |publisher=Rowman & Littlefield |year=2001 |isbn=978-0-7425-0019-8 |page=[https://archive.org/details/northamericahist00mcil/page/61 61] |access-date=October 25, 2015}}</ref> The [[California Gold Rush]] of 1848–1849 spurred a huge migration of white settlers to the Pacific coast, leading to even more confrontations with Native populations. One of the most violent, the [[California genocide]] of thousands of Native inhabitants, lasted into the early 1870s,<ref>{{cite web|url=https://newsroom.ucla.edu/stories/revealing-the-history-of-genocide-against-californias-native-americans|title=Revealing the history of genocide against California's Native Americans|last=Wolf|first=Jessica|website=UCLA Newsroom|language=en|access-date=July 8, 2018}}</ref><ref>{{Cite book|last=Madley |first=Benjamin |date=2016 |title=An American Genocide: The United States and the California Indian Catastrophe, 1846-1873. |publisher=Yale University Press |url=https://archive.org/details/americangenocide0000madl |url-access=registration |isbn= 9780300230697}}</ref> just as additional western territories and states were created.<ref name="Rawls1999">{{cite book|author=Rawls, James J.|title=A Golden State: Mining and Economic Development in Gold Rush California|url=https://books.google.com/books?id=UPUsIaHZTm0C&pg=PA20|year=1999|publisher=University of California Press|isbn=978-0-520-21771-3|page=20}}</ref>

=== Civil War ===
{{Main|History of the United States (1849–1865)|American Civil War}}
[[File:US map 1864 Civil War divisions.svg|thumb|Division of the states during the [[American Civil War]]:
{{legend|#204A87|[[Union (American Civil War)|Union states]]}}
{{legend|#729FCF|[[Border states (American Civil War)|Border states]]}}
{{legend|#A40000|[[Confederate States of America|Confederate states]]}}
{{legend|#D3D7CF|[[Territories of the United States|Territories]]}}]]

During the colonial period, [[Slavery in the colonial history of the United States|slavery was legal in the American colonies]], though the practice began to be significantly questioned during the American Revolution.{{sfnm|1a1=Walker Howe|1y=2007|1p=52–54|2a1=Wright|2y=2022}} States in [[Northern United States|The North]] enacted [[Abolitionism in the United States|abolition laws]],{{sfnm|1a1=Walker Howe|1y=2007|1p=52–54|2a1=Rodriguez|2y=2015|2p=XXXIV|3a1=Wright|3y=2022}} though support for slavery strengthened in [[Southern United States|Southern states]], as inventions such as the [[cotton gin]] made the institution increasingly profitable for [[Planter class|Southern elites]].<ref>[[United States#Walton|Walton, 2009]], p. 43</ref><ref>[[United States#Gordon|Gordon, 2004]], pp. 27,29</ref>{{sfn|Walker Howe|2007|p=478, 481–482, 587–588}} This [[Slave states and free states|sectional conflict]] regarding slavery [[Origins of the American Civil War|culminated]] in the [[American Civil War]] (1861–1865).<ref>{{cite book |last=Murray |first=Stuart |url=https://books.google.com/books?id=bJ_sy7mmmxQC&pg=PA76 |title=Atlas of American Military History |publisher=Infobase Publishing |year=2004 |isbn=978-1-4381-3025-5 |page=76 |access-date=October 25, 2015}} {{cite book |last=Lewis |first=Harold T. |url=https://books.google.com/books?id=kr-xNru5vZkC&pg=PA53 |title=Christian Social Witness |publisher=Rowman & Littlefield |year=2001 |isbn=978-1-56101-188-9 |page=53}}</ref><ref name="Woods 2012 pp. 415–4392">{{cite journal |last=Woods |first=Michael E. |year=2012 |title=What Twenty-First-Century Historians Have Said about the Causes of Disunion: A Civil War Sesquicentennial Review of the Recent Literature |url=http://www.jstor.org/stable/44306803 |journal=The Journal of American History |publisher=[Oxford University Press, Organization of American Historians] |volume=99 |issue=2 |pages=415–439 |doi=10.1093/jahist/jas272 |issn=0021-8723 |jstor=44306803 |access-date=April 29, 2023}}</ref>

Eleven slave states [[seceded]] and formed the [[Confederate States of America]], while the other states remained in [[Union (American Civil War)|the Union]].<ref name="Silkenat 2019 p. 252">{{cite book |last=Silkenat |first=D. |url=https://books.google.com/books?id=nHWKDwAAQBAJ&pg=PA25 |title=Raising the White Flag: How Surrender Defined the American Civil War |publisher=University of North Carolina Press |year=2019 |isbn=978-1-4696-4973-3 |series=Civil War America |page=25 |access-date=April 29, 2023}}</ref> War broke out in April 1861 after the Confederacy [[Battle of Fort Sumter|bombarded Fort Sumter]].<ref>{{cite book |last=Vinovskis |first=Maris |title=Toward A Social History of the American Civil War: Exploratory Essays |date=1990 |publisher=Cambridge University Press |isbn=978-0-521-39559-5 |location=Cambridge; New York |page=4}}</ref> After the January 1863 [[Emancipation Proclamation]], many freed slaves joined the Union Army.<ref>{{cite web|url=https://www.archives.gov/education/lessons/blacks-civil-war/ |title=The Fight for Equal Rights: Black Soldiers in the Civil War|work=[[National Archives and Records Administration|U.S. National Archives and Records Administration]]|date=August 15, 2016|quote=By the end of the Civil War, roughly 179,000 black men (10% of the Union Army) served as soldiers in the U.S. Army and another 19,000 served in the Navy.}}</ref> The war [[Turning point of the American Civil War|began to turn in the Union's favor]] following the 1863 [[Siege of Vicksburg]] and [[Battle of Gettysburg]], and the Confederacy surrendered in 1865 after the Union's victory in the [[Battle of Appomattox Court House]].<ref>Davis, Jefferson. [https://archive.org/stream/ashorthistoryco00davigoog#page/n544/mode/2up/search/surrender+at+Appomattox ''A Short History of the Confederate States of America''], 1890, 2010. {{ISBN|978-1-175-82358-8}}. Available free online as an ebook. Chapter LXXXVIII, "Re-establishment of the Union by force", p. 503. Retrieved March 14, 2012.</ref>

The [[Reconstruction era]] followed the war. After [[Assassination of Abraham Lincoln|the assassination]] of President [[Abraham Lincoln]], [[Reconstruction Amendments]] were passed to [[Civil rights movement (1865–1896)|protect the rights of African Americans]]. National infrastructure, including [[First transcontinental telegraph|transcontinental telegraph]] and [[First transcontinental railroad|railroads]], spurred growth in the [[American frontier]].<ref name="Black2011kj2">{{cite book |last=Black |first=Jeremy |url=https://books.google.com/books?id=EIst_CSWOqIC&pg=PA275 |title=Fighting for America: The Struggle for Mastery in North America, 1519–1871 |publisher=Indiana University Press |year=2011 |isbn=978-0-253-35660-4 |page=275 |author-link=Jeremy Black (historian)}}</ref>

=== Post-Civil War era ===
{{Main|History of the United States (1865–1917)}}
[[File:Emigrants (i.e. immigrants) landing at Ellis Island -.webm|thumb|An [[Edison Studios]] film showing immigrants arriving at [[Ellis Island]] in [[New York Harbor]], a major point of entry for European [[Immigration to the United States|immigrants]] in the late 19th and early 20th centuries<ref name="PriceBenton-Short2008">{{cite book|first1=Marie|last1=Price|first2=Lisa|last2=Benton-Short|title=Migrants to the Metropolis: The Rise of Immigrant Gateway Cities|url=https://books.google.com/books?id=_Tb5HMB63xAC&pg=PA51|year=2008|publisher=Syracuse University Press|isbn=978-0-8156-3186-6|page=51}}</ref><ref>{{Cite web |date=March 4, 2020 |title=Overview + History {{!}} Ellis Island |url=https://www.statueofliberty.org/ellis-island/overview-history/ |access-date=September 10, 2021 |website=Statue of Liberty & Ellis Island |language=en}}</ref>]]

From 1865 through 1917 an unprecedented stream of immigrants arrived in the United States, including 24.4 million from Europe.<ref>U.S. Bureau of the Census, ''Historical Statistics of the United States'' (1976) series C89-C119, pp&nbsp;105–9</ref> Most came through the [[Port of New York and New Jersey|port of New York City]], and New York City and other large cities on the [[East Coast of the United States|East Coast]] became home to large [[History of the Jews in the United States|Jewish]], [[Irish Americans|Irish]], and [[Italian Americans|Italian]] populations, while many [[German Americans|Germans]] and Central Europeans moved to the [[Midwestern United States|Midwest]]. At the same time, about one million [[French-Canadian Americans|French Canadians]] migrated from [[Quebec]] to [[New England]].<ref>Stephan Thernstrom, ed., ''Harvard Encyclopedia of American Ethnic Groups'' (1980) covers the history of all the main groups</ref> During the [[Great Migration (African American)|Great Migration]], millions of African Americans [[Jim Crow economy|left the rural South]] for urban areas in the North.<ref>{{Cite web |date=May 20, 2021 |title=The Great Migration (1910–1970) |url=https://www.archives.gov/research/african-americans/migrations/great-migration |publisher=National Archives}}</ref> Alaska was [[Alaska Purchase|purchased]] from [[Russian Empire|Russia]] in 1867.<ref>{{cite web |title=Purchase of Alaska, 1867 |url=https://history.state.gov/milestones/1866-1898/alaska-purchase |access-date=December 23, 2014 |website=Office of the Historian |publisher=U.S. Department of State}}</ref>

The [[Compromise of 1877]] effectively ended Reconstruction and [[Redeemers|white supremacists took local control of Southern politics]].<ref>{{cite book |last=Woodward |first=C. Vann |title=Reunion and Reaction: The Compromise of 1877 and the End of Reconstruction |date=1991 |publisher=Oxford University Press |location=United Kingdom}}</ref><ref>{{cite web |author1=Drew Gilpin Faust |author-link=Drew Gilpin Faust |author2=Eric Foner |author2-link=Eric Foner |author3=Clarence E. Walker |author3-link=Clarence E. Walker |title=White Southern Responses to Black Emancipation |url=http://www.pbs.org/wgbh/americanexperience/features/reconstruction-white-southern-responses-black-emancipation/ |work=[[American Experience]]}}</ref> African Americans endured a period of heightened, overt racism following Reconstruction, a time often called the [[nadir of American race relations]].<ref name="ReferenceA2">{{cite book |last=Trelease |first=Allen W. |title=White Terror: The Ku Klux Klan Conspiracy and Southern Reconstruction |publisher=Harper & Row |year=1979 |isbn=0-313-21168-X |location=New York}}</ref><ref>{{cite book |author=Shearer Davis Bowman |url=https://archive.org/details/masterslordsmid10000bowm |title=Masters and Lords: Mid-19th-Century U.S. Planters and Prussian Junkers |publisher=Oxford UP |year=1993 |isbn=978-0-19-536394-4 |page=[https://archive.org/details/masterslordsmid10000bowm/page/221 221] |url-access=registration}}</ref> A series of Supreme Court decisions, including [[Plessy v. Ferguson]], emptied the Fourteenth and Fifteenth Amendments of their force, allowing [[Jim Crow laws]] in the South to remain unchecked, [[sundown town]]s in the Midwest, and [[racial segregation in the United States|segregation]] in cities across the country, which would be reinforced by the policy of [[redlining]] later adopted by the federal [[Home Owners' Loan Corporation]].<ref>{{cite journal |title=Plessy's Legacy: The Government's Role in the Development and Perpetuation of Segregated Neighborhoods |last=Ware |first=Leland |journal=RSF: The Russell Sage Foundation Journal of the Social Sciences |date=February 2021 |pages=92–109 |volume=7 |issue=1 |doi=10.7758/rsf.2021.7.1.06 |s2cid=231929202 }}</ref>

[[Second Industrial Revolution|An explosion of technological advancement]] accompanied by the exploitation of cheap immigrant labor<ref>{{cite journal |last1=Hirschman |first1=Charles |last2=Mogford |first2=Elizabeth |date=1 December 2009 |title=Immigration and the American Industrial Revolution From 1880 to 1920 |journal=Social Science Research |volume=38 |issue=4 |pages=897–920 |doi=10.1016/j.ssresearch.2009.04.001 |issn=0049-089X |pmc=2760060 |pmid=20160966}}</ref> led to [[Gilded Age|rapid economic development]] during the late 19th and early 20th centuries, allowing the United States to outpace England, France, and Germany combined.<ref>{{cite book |last1=Carson |first1=Thomas |last2=Bonk |first2=Mary |title=Gale Encyclopedia of U.S. Economic History |date=1999 |publisher=Gale |chapter=Industrial Revolution}}</ref><ref>{{cite book |last1=Riggs |first1=Thomas |title=Gale Encyclopedia of U.S. Economic History Vol. 3 |date=2015 |publisher=Gale |page=1179 |edition=2}}</ref> This fostered the amassing of power by [[Robber baron (industrialist)|a few prominent industrialists]], largely by their formation of [[Trust (business)|trusts]] and [[Monopoly|monopolies]] to prevent competition.<ref name="Atlantic2">{{Cite journal |last=Dole |first=Charles F. |year=1907 |title=The Ethics of Speculation |journal=[[The Atlantic Monthly]] |volume=C |issue=December 1907 |pages=812–818}}</ref> [[Tycoon]]s led the nation's expansion in the [[History of rail transportation in the United States|railroad]], [[History of the petroleum industry in the United States|petroleum]], and [[History of the steel industry (1850–1970)|steel]] industries. The United States emerged as a pioneer of the [[Automotive industry in the United States|automotive industry]].<ref>{{cite web |author1=The Pit Boss |date=February 26, 2021 |title=The Pit Stop: The American Automotive Industry Is Packed With History |url=https://pitstop.rumbleon.com/american-automotive-history |access-date=December 5, 2021 |website=Rumble On}}</ref> These changes were accompanied by significant increases in [[economic inequality]], [[How the Other Half Lives|slum conditions]], and [[List of incidents of civil unrest in the United States|social unrest]], creating the environment for [[Labor history of the United States|labor unions to begin to flourish]].<ref>Tindall, George Brown and Shi, David E. (2012). ''America: A Narrative History (Brief Ninth Edition) (Vol. 2).'' [[W. W. Norton & Company]]. {{ISBN|978-0-393-91267-8}} p. 589</ref><ref>[[United States#Zinn|Zinn, 2005]], pp. 321–357</ref><ref name="Fraser2">{{cite book |last=Fraser |first=Steve |title=The Age of Acquiescence: The Life and Death of American Resistance to Organized Wealth and Power |publisher=[[Little, Brown and Company]] |year=2015 |isbn=978-0-316-18543-1 |page=66}}</ref> This period eventually ended with the advent of the [[Progressive Era]], which was characterized by significant reforms.<ref name="Aldrich2">Aldrich, Mark. ''Safety First: Technology, Labor and Business in the Building of Work Safety, 1870-1939.'' Baltimore: Johns Hopkins University Press, 1997. {{ISBN|0-8018-5405-9}}</ref><ref>{{cite web |title=Progressive Era to New Era, 1900-1929 {{!}} U.S. History Primary Source Timeline {{!}} Classroom Materials at the Library of Congress {{!}} Library of Congress |url=https://www.loc.gov/classroom-materials/united-states-history-primary-source-timeline/progressive-era-to-new-era-1900-1929/overview/ |access-date=11 November 2023 |website=Library of Congress, Washington, D.C. 20540 USA}}</ref>

=== Rise as a superpower ===
{{Main|History of the United States (1917–1945)}}
[[File:TrinityDetonation1945GIF.gif|thumb|The [[Trinity (nuclear test)|Trinity nuclear test]] in 1945, part of the [[Manhattan Project]] and the first detonation of a [[nuclear weapon]]. The World Wars permanently ended the country's policy of [[United States non-interventionism|isolationism]] and left it as a world [[superpower]].]]

Pro-American elements in Hawaii [[Overthrow of the Kingdom of Hawaii|overthrew]] the [[Hawaiian Kingdom|Hawaiian monarchy]]; the islands were [[Newlands Resolution|annexed]] in 1898. [[Puerto Rico]], [[Guam]], and the [[Philippines]] were ceded by Spain following the [[Spanish–American War]].<ref>{{cite web |title=The Spanish–American War, 1898 |url=https://history.state.gov/milestones/1866-1898/spanish-american-war |access-date=December 24, 2014 |website=Office of the Historian |publisher=U.S. Department of State}}</ref> [[American Samoa]] was acquired by the United States in 1900 after the [[Second Samoan Civil War]].<ref>Ryden, George Herbert. ''The Foreign Policy of the United States in Relation to Samoa''. New York: Octagon Books, 1975.</ref> The [[United States Virgin Islands|U.S. Virgin Islands]] were purchased from [[Denmark]] in 1917.<ref>{{cite web |title=Virgin Islands History |url=https://www.vinow.com/general_usvi/history/ |access-date=January 5, 2018 |publisher=Vinow.com}}</ref> The United States entered [[World War I]] alongside the [[Allies of World War I]], helping to turn the tide against the [[Central Powers]].<ref>McDuffie, Jerome; Piggrem, Gary Wayne; Woodworth, Steven E. (2005). ''U.S. History Super Review''. Piscataway, NJ: Research & Education Association. p. 418. {{ISBN|978-0-7386-0070-3}}.</ref> In 1920, [[Nineteenth Amendment to the United States Constitution|a constitutional amendment]] granted nationwide [[Women's suffrage in the United States|women's suffrage]].<ref>{{Cite journal |last1=Larson |first1=Elizabeth C. |last2=Meltvedt |first2=Kristi R. |year=2021 |title=Women's suffrage: fact sheet |url=https://crsreports.congress.gov/product/details?prodcode=R45805 |journal=CRS Reports (Library of Congress. Congressional Research Service) |series=Report / Congressional Research Service |access-date=August 9, 2023}}</ref> During the 1920s and 30s, radio for [[mass communication]] and the invention of early television transformed communications nationwide.{{sfn|Winchester|2013|pp=410–411}} The [[Wall Street Crash of 1929]] triggered the [[Great Depression in the United States|Great Depression]], which President [[Franklin D. Roosevelt]] responded to with [[New Deal]] social and economic policies.<ref>{{cite book |last1=Axinn |first1=June |title=Social Welfare: A History of the American Response to Need |last2=Stern |first2=Mark J. |publisher=Allyn & Bacon |year=2007 |isbn=978-0-205-52215-6 |edition=7th |location=Boston}}</ref><ref>{{cite book |author=James Noble Gregory |url=https://books.google.com/books?id=qNdtGwnXYrIC |title=American Exodus: The Dust Bowl Migration and Okie Culture in California |publisher=Oxford University Press |year=1991 |isbn=978-0-19-507136-8 |access-date=October 25, 2015}} {{cite web |author=<!-- Staff writer(s); no by-line. --> |year=2013 |title=Mass Exodus From the Plains |url=https://www.pbs.org/wgbh/americanexperience/features/general-article/dustbowl-mass-exodus-plains/ |access-date=October 5, 2014 |website=American Experience |publisher=WGBH Educational Foundation}} {{cite web |last1=Fanslow |first1=Robin A. |date=April 6, 1997 |title=The Migrant Experience |url=https://memory.loc.gov/ammem/afctshtml/tsme.html |access-date=October 5, 2014 |website=American Folklore Center |publisher=Library of Congress}} {{cite book |last=Stein |first=Walter J. |url=https://books.google.com/books?id=hGuGAAAAIAAJ |title=California and the Dust Bowl Migration |publisher=Greenwood Press |year=1973 |isbn=978-0-8371-6267-6 |access-date=October 25, 2015}}</ref>

[[United States non-interventionism before entering World War II|At first neutral]] during [[World War II]], the U.S. began [[Lend-Lease|supplying war materiel]] to the [[Allies of World War II]] in March 1941 and entered the war in December after the [[Empire of Japan]]'s attack on [[Attack on Pearl Harbor|Pearl Harbor]].<ref>The official WRA record from 1946 states that it was 120,000 people. See {{cite book |author=[[War Relocation Authority]] |url=https://ddr.densho.org/ddr-densho-282-5/ |title=The Evacuated People: A Quantitative Study |year=1946 |page=8}} This number does not include people held in other camps such as those run by the DoJ or U.S. Army. Other sources may give numbers slightly more or less than 120,000.</ref><ref name="Pearl Harbor2">{{cite web |last1=Yamasaki |first1=Mitch |title=Pearl Harbor and America's Entry into World War II: A Documentary History |url=https://www.hawaiiinternment.org/static/ush_yamasaki_documentary_history.pdf |archive-url=https://web.archive.org/web/20141213122046/https://www.hawaiiinternment.org/static/ush_yamasaki_documentary_history.pdf |archive-date=December 13, 2014 |access-date=January 14, 2015 |publisher=World War II Internment in Hawaii}}</ref> The U.S. [[Manhattan Project|developed the first nuclear weapons]] and [[Atomic bombings of Hiroshima and Nagasaki|used them against the Japanese cities of Hiroshima and Nagasaki]] in August 1945, ending the war.<ref>{{Cite news |title=Why did Japan surrender in World War II? |language=en |newspaper=The Japan Times |url=https://www.japantimes.co.jp/opinion/2016/08/06/commentary/japan-surrender-world-war-ii/ |access-date=February 8, 2017}}</ref><ref>Pacific War Research Society (2006). ''Japan's Longest Day''. New York: Oxford University Press. {{ISBN|978-4-7700-2887-7}}.</ref> The United States was one of the "[[Four Policemen]]" who met to plan the postwar world, alongside the United Kingdom, [[Soviet Union]], and [[Republic of China (1912–1949)|China]].{{sfn|Hoopes|Brinkley|1997|p=100}}{{sfn|Gaddis|1972|p=25}} The U.S. emerged relatively unscathed from the war, with even greater economic and international political influence.<ref>Kennedy, Paul (1989). ''The Rise and Fall of the Great Powers''. New York: Vintage. p. 358. {{ISBN|978-0-679-72019-5}}</ref>

=== Cold War ===
{{Main|Cold War}}
{{Further|History of the United States (1945–1964)|History of the United States (1964–1980)|History of the United States (1980–1991)}}
[[File:Reagan and Gorbachev signing.jpg|thumb|[[Mikhail Gorbachev]] and [[Ronald Reagan]] sign the [[Intermediate-Range Nuclear Forces Treaty]] at the [[White House]] in 1987.]]
After World War II, the United States entered the [[Cold War]], where geopolitical tensions between the U.S. and the Soviet Union led the two countries to dominate world affairs.<ref>{{Cite book |last=Sempa |first=Francis |url=https://books.google.com/books?id=Px4uDwAAQBAJ |title=Geopolitics: From the Cold War to the 21st Century |date=12 July 2017 |publisher=Routledge |isbn=978-1-351-51768-3}}</ref> The U.S. engaged in [[United States involvement in regime change|regime change]] against governments perceived to be aligned with the Soviet Union, and competed in the [[Space Race]], culminating in the [[Apollo 11|first crewed Moon landing]] in 1969.<ref name="Blakemore-20192">{{cite web |last=Blakemore |first=Erin |date=March 22, 2019 |title=What was the Cold War? |url=https://www.nationalgeographic.com/culture/topics/reference/cold-war/ |url-status=dead |archive-url=https://web.archive.org/web/20190401192349/https://www.nationalgeographic.com/culture/topics/reference/cold-war/ |archive-date=April 1, 2019 |access-date=August 28, 2020 |website=National Geographic |language=en}}</ref><ref>Mark Kramer, "The Soviet Bloc and the Cold War in Europe," in {{Cite book |url=https://books.google.com/books?id=EyNcCwAAQBAJ&pg=PT174 |title=A Companion to Europe Since 1945 |publisher=Wiley |year=2014 |isbn=978-1-118-89024-0 |editor-last=Larresm |editor-first=Klaus |page=79}}</ref><ref>[[United States#Blakeley|Blakeley, 2009]], [https://books.google.com/books?id=rft8AgAAQBAJ&pg=PA92 p. 92]</ref><ref name="Proxy2">{{cite book |last=Collins |first=Michael |url=https://archive.org/details/liftoff00coll |title=Liftoff: The Story of America's Adventure in Space |publisher=Grove Press |year=1988 |isbn=978-0-8021-1011-4 |location=New York |author-link=Michael Collins (astronaut) |url-access=registration}}</ref>

Domestically, [[Post–World War II economic expansion|the U.S. experienced economic growth]], [[Urbanization in the United States|urbanization]], and [[Mid-20th century baby boom|population growth following World War II]].{{sfn|Winchester|2013|pp=305–308}} The [[civil rights movement]] emerged, with [[Martin Luther King Jr.]] becoming a prominent leader in the early 1960s.<ref>{{cite web |title=The Civil Rights Movement |url=https://www.pbs.org/johngardner/chapters/4b.html |access-date=January 5, 2019 |publisher=PBS}}</ref> The [[Great Society]] plan of President [[Lyndon Johnson]]'s administration resulted in groundbreaking and broad-reaching laws, policies and a constitutional amendment to counteract some of the worst effects of lingering [[institutional racism]].<ref>{{cite book|first= Alan|last=Brinkley|chapter= Great Society |title=The Reader's Companion to American History|date=January 24, 1991 |editor1=Eric Foner|editor2=John Arthur Garraty|isbn=0-395-51372-3|publisher=Houghton Mifflin Books|page=472}}</ref> The [[Counterculture of the 1960s|counterculture movement]] in the U.S. brought significant social changes, including the liberalization of attitudes toward [[recreational drug use]] and [[Sexual revolution|sexuality]]. It also encouraged [[Draft evasion in the Vietnam War|open defiance of the military draft]] (leading to the [[Conscription#By country|end of conscription]] in 1973) and [[Opposition to United States involvement in the Vietnam War|wide opposition]] to [[United States in the Vietnam War|U.S. intervention in Vietnam]] (with the U.S. totally withdrawing in 1975).<ref>{{cite web |author=Svetlana Ter-Grigoryan |date=February 12, 2022 |title=The Sexual Revolution Origins and Impact |url=https://study.com/learn/lesson/sexual-liberation-movement-origin-timeline-impact-revolution.html |access-date=April 27, 2023 |website=study.com}}</ref><ref>{{cite magazine |last=Levy |first=Daniel |date=January 19, 2018 |title=Behind the Protests Against the Vietnam War in 1968 |url=https://time.com/5106608/protest-1968/?amp=true |magazine=[[Time (magazine)|Time]] |access-date=May 5, 2021}}</ref><ref>{{Cite web |date=August 25, 2022 |title=Playboy: American Magazine |url=https://www.britannica.com/topic/Playboy |access-date=February 2, 2023 |website=[[Encyclopædia Britannica]] |quote=...the so-called sexual revolution in the United States in the 1960s, marked by greatly more permissive attitudes toward sexual interest and activity than had been prevalent in earlier generations.}}</ref> The societal shift in the roles of women partly resulted in large increases in female labor participation in the 1970s, and by 1985 the majority of women aged 16 and older were employed.<ref>{{cite web|title=Women in the Labor Force: A Databook|url=https://www.bls.gov/cps/wlf-databook-2012.pdf|publisher=U.S. Bureau of Labor Statistics|access-date=March 21, 2014|page=11|year=2013}}</ref> The late 1980s and early 1990s saw the [[Revolutions of 1989|collapse of the Warsaw Pact]] and the [[dissolution of the Soviet Union]], which marked the end of the Cold War and solidified the U.S. as the world's sole superpower.<ref name="Gaidar2">{{cite book |last=Gaĭdar |first=E.T. |url={{GBUrl|bDSfnxYjVwAC|pg=PA102}} |title=Collapse of an Empire: Lessons for Modern Russia |publisher=[[Brookings Institution#Publications|Brookings Institution Press]] |year=2007 |isbn=978-0-8157-3114-6 |location=Washington, D.C. |pages=190–205}}</ref><ref>{{cite book |last=Howell |first=Buddy Wayne |title=The Rhetoric of Presidential Summit Diplomacy: Ronald Reagan and the U.S.-Soviet Summits, 1985–1988 |publisher=Texas A&M University |year=2006 |isbn=978-0-549-41658-6 |page=352}}</ref><ref>{{cite book |last=Kissinger |first=Henry |url=https://books.google.com/books?id=0IZboamhb5EC&pg=PA731 |title=Diplomacy |publisher=Simon & Schuster |year=2011 |isbn=978-1-4391-2631-8 |pages=781–784 |author-link=Henry Kissinger |access-date=October 25, 2015}} {{cite book |last=Mann |first=James |url=https://books.google.com/books?id=BgZyXNIrvB4C&pg=PT12 |title=The Rebellion of Ronald Reagan: A History of the End of the Cold War |publisher=Penguin |year=2009 |isbn=978-1-4406-8639-9 |page=432}}</ref><ref>[[United States#Hayes|Hayes, 2009]]</ref>

=== Contemporary ===
{{Main|History of the United States (1991–2008)|History of the United States (2008–present)}}
[[File:Explosion_following_the_plane_impact_into_the_South_Tower_(WTC_2)_-_B6019~11.jpg|thumb|The [[World Trade Center (1973–2001)|Twin Towers]] in New York City during the [[September 11 attacks]] of 2001]]
The 1990s saw the [[1990s United States boom|longest recorded economic expansion in American history]], [[Crime in the United States|a dramatic decline in crime]], and [[Digital Revolution|advances in technology]], with the [[World Wide Web]], the evolution of the [[Pentium (original)|Pentium microprocessor]] in accordance with [[Moore's law]], rechargeable [[Lithium-ion battery|lithium-ion batteries]], the first [[gene therapy]] trial, and [[cloning]] all emerging and being improved upon throughout the decade. The [[Human Genome Project]] was formally launched in 1990, while [[Nasdaq]] became the first stock market in the United States to trade online in 1998.<ref>{{Cite web |last=((CFI Team)) |title=NASDAQ |url=https://corporatefinanceinstitute.com/resources/career-map/sell-side/capital-markets/nasdaq/ |url-status=live |archive-url=https://web.archive.org/web/20231211163114/https://corporatefinanceinstitute.com/resources/career-map/sell-side/capital-markets/nasdaq/ |archive-date=2023-12-11 |access-date=2023-12-11 |website=Corporate Finance Institute |language=en-US}}</ref> In 1991, [[Coalition of the Gulf War|an American-led international coalition of states]] expelled an [[Ba'athist Iraq|Iraqi]] invasion force from [[Kuwait]] in the [[Gulf War]].<ref>{{cite book|last=Holsti|first=Ole R.|author-link=Ole R. Holsti|title=American Public Opinion on the Iraq War|page=20|chapter=The United States and Iraq before the Iraq War|date=2011-11-07|publisher=[[University of Michigan Press]]|isbn=978-0-472-03480-2}}</ref>

The [[September 11 attacks|September 11, 2001 attacks]] by the [[Pan-Islamism|pan-Islamist]] militant organization [[al-Qaeda]] led to the [[war on terror]] and subsequent military interventions [[War in Afghanistan (2001–2021)|in Afghanistan]] and [[Iraq War|Iraq]].<ref>{{cite news |author=Walsh, Kenneth T. |date=December 9, 2008 |title=The 'War on Terror' Is Critical to President George W. Bush's Legacy |newspaper=U.S. News & World Report |url=https://www.usnews.com/news/articles/2008/12/09/the-war-on-terror-is-critical-to-president-george-w-bushs-legacy |access-date=March 6, 2013}} {{cite book |last=Atkins |first=Stephen E. |url=https://books.google.com/books?id=PDDIgWRN_HQC&pg=PA210 |title=The 9/11 Encyclopedia: Second Edition |publisher=ABC-CLIO |year=2011 |isbn=978-1-59884-921-9 |page=872 |access-date=October 25, 2015}}</ref><ref>{{cite news |last=Wong |first=Edward |date=February 15, 2008 |title=Overview: The Iraq War |newspaper=The New York Times |url=https://www.nytimes.com/ref/timestopics/topics_iraq.html |access-date=March 7, 2013}} {{cite book |last=Johnson |first=James Turner |url=https://books.google.com/books?id=SF7U27JsLC4C&q=iraq+invasion+removes+hussein |title=The War to Oust Saddam Hussein: Just War and the New Face of Conflict |publisher=Rowman & Littlefield |year=2005 |isbn=978-0-7425-4956-2 |page=159 |access-date=October 25, 2015}} {{cite news |author=Durando, Jessica |author2=Green, Shannon Rae |date=December 21, 2011 |title=Timeline: Key moments in the Iraq War |newspaper=USA Today |agency=Associated Press |url=https://usatoday30.usatoday.com/news/world/iraq/story/2011-12-21/iraq-war-timeline/52147680/1 |url-status=dead |access-date=March 7, 2013 |archive-url=https://web.archive.org/web/20200904084312/https://usatoday30.usatoday.com/news/world/iraq/story/2011-12-21/iraq-war-timeline/52147680/1 |archive-date=September 4, 2020}}</ref> The [[Cultural influence of the September 11 attacks|cultural impact of the attacks]] was profound and long-lasting.

The [[2000s United States housing bubble|U.S. housing bubble]] culminated in 2007 with the [[Great Recession]], the largest economic contraction since the Great Depression.<ref>{{Cite news |last1=Hilsenrath |first1=Jon |last2=Ng |first2=Serena |last3=Paletta |first3=Damian |date=September 18, 2008 |title=Worst Crisis Since '30s, With No End Yet in Sight |work=[[The Wall Street Journal]] |url=https://www.wsj.com/articles/SB122169431617549947 |url-status=live |url-access=subscription |access-date=July 28, 2023 |archive-url=https://web.archive.org/web/20141225040616/https://www.wsj.com/articles/SB122169431617549947 |archive-date=December 25, 2014 |issn=1042-9840 |oclc=781541372}}</ref> Coming to a head in the 2010s, [[Political polarization in the United States|political polarization]] increased as sociopolitical debates on cultural issues dominated politics.<ref>{{Cite web |last=Hamid |first=Shadi |date=2022-01-08 |title=The Forever Culture War |url=https://www.theatlantic.com/ideas/archive/2022/01/republicans-democrats-forever-culture-war/621184/ |access-date=2023-10-01 |website=[[The Atlantic]] |language=en}}</ref> This polarization was capitalized upon in the [[January 6 United States Capitol attack|January 2021 Capitol attack]],<ref name="Initial Encyclopedia Britannica">{{cite encyclopedia |last=Duignan |first=Brian |date=2021-08-04 |title=January 6 U.S. Capitol attack |url=https://www.britannica.com/event/January-6-U-S-Capitol-attack |url-status=live |access-date=2021-09-22 |encyclopedia=[[Encyclopædia Britannica]] |quote=Because its object was to prevent a legitimate president-elect from assuming office, the attack was widely regarded as an insurrection or attempted coup d'état.|language=en |archive-url=https://web.archive.org/web/20230117232629/https://www.britannica.com/event/January-6-U-S-Capitol-attack |archive-date=2023-01-17}}</ref> when a mob of protesters entered the [[United States Capitol|U.S. Capitol]] and attempted to prevent the peaceful transfer of power.<ref>{{cite news |last1=Rutenberg |first1=Jim |last2=Becker |first2=Jo |last3=Lipton |first3=Eric |last4=Haberman |first4=Maggie |last5=Martin |first5=Jonathan |last6=Rosenberg |first6=Matthew |last7=Schmidt |first7=Michael S. |title=77 Days: Trump's Campaign to Subvert the Election |url=https://www.nytimes.com/2021/01/31/us/trump-election-lie.html |work=The New York Times |date=31 January 2021 |archiveurl=https://archive.today/20220618170015/https://www.nytimes.com/2021/01/31/us/trump-election-lie.html |archivedate=2022-06-18 |url-status=live}}</ref>