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Military history of the United States

The Military history of the United States spans a period of less than two and a half centuries. Over the course of those years, the United States grew from an alliance of thirteen British colonies without a professional military, to Earth's sole military superpower as of 2005.



Main articles: Military of the United States and Military budget in the United States

Until the Constitutional Convention, the military presence in what became known as the United States was organized by each U.S. state as a voluntary or conscripted militia. As of 2005, the U.S. military consisted of a army, navy, air force and marine corps under the command of the United States Department of Defense. There also is the United States Coast Guard, which is controlled by the Department of Homeland Security. In each of these branches of miliary, the President of the United States is the commander in chief of the armed forces. In addition, each state has a national guard commanded by the state's governor and coordinated by the National Guard Bureau. The President of the United States has the authority during national emergencies to assume control of individual state national guard units.

The United States Constitution provided authority for the Congress to levy taxes and to raise a navy and national militia. Federal legislation eventually led to the modern nationalized system of military in the country. Historically, the amount of money the U.S. government spends on the military has often been a politically contentious issue.


Colonial wars (1620–1774)

The beginning of the United States military lies in civilian frontiersmen, armed for hunting and basic survival in the wilderness. These were organized into local militias for small military operations, mostly against Native American tribes but also to resist possible raids by the small military forces of neighboring European colonies. They relied on the support of the British regular army and navy for any serious military operation.

In the early years of the British colonization of North America, military action in the colonies that would become United States were the result of conflicts with Native Americans, such as in the Pequot War of 1637 and King Philip's War in 1675. Slave uprisings such as the Stono Rebellion in 1739, and inter-colonial conflicts, such as the Pennamite Wars and the activities of the Green Mountain Boys, were also a part of the colonial military experience.

Beginning in 1689, the colonies also frequently became involved in a series of wars between Great Britain and France for control of North America. The war the colonists called the "French and Indian War," which was inadvertently started in the backwoods of Pennsylvania by a young Virginian named George Washington, had a significant impact on the emergence of the American Revolution.

War of Independence (1774–1783)

There were many causes that led to the American Revolutionary War, but political tensions between Great Britain and her colonies became a crisis in 1774 when the British placed the province of Massachusetts under martial law. While shooting began at Lexington and Concord in 1775, the Continental Congress appointed George Washington as commander-in-chief of the newly created Continental Army, which was augmented throughout the war by colonial militia. General Washington was no great battlefield tactician—he lost more battles than he won—but his overall strategy proved to be sound: keep the army intact, wear down British resolve, and avoid decisive battles except to exploit enemy mistakes.

The British, for their part, lacked both a unified command and a clear strategy for winning. With the use of the Royal Navy, the British were able to capture coastal cities, but control of the countryside eluded them. An invasion from Canada in 1777 ended with the disastrous surrender of a British army at Saratoga. France entered the war against Great Britain after Saratoga, finally convinced that the Americans could actually win.

The involvement of France (and then Spain) greatly complicated the British war effort. A shift in focus to the southern American colonies resulted in a string of victories for the British, but guerilla warfare and the tenacity of General Nathanael Greene's army prevented the British from making strategic headway. A French naval victory in the Chesapeake finally offered the chance Washington had long waited for, and a British army was trapped and compelled to surrender at Yorktown in 1781, leading to the Treaty of Paris in 1783 that recognized the independence of the United States.

Since many Americans of the revolutionary generation had a strong distrust of permanent (or "standing") armies, the Continental Army was quickly disbanded after the Revolution. General Washington, who throughout the war deferred to elected officials, averted a potential crisis and submitted his resignation as commander-in-chief to Congress after the war, establishing a tradition of civil control of the U.S. military.

Early nationhood (1784–1820)

Following the American Revolution, the United States faced potential military conflict on the high seas as well as on the frontiers. In the Treaty of Paris, the British had ceded the lands between the Appalachian Mountains and the Mississippi River to the United States, without consulting the Native Americans who lived there. Because many of the tribes had fought as allies of the British, the United States compelled the Indians to sign away lands in postwar treaties, and began dividing up these lands for settlement. This provoked a war in the Northwest Territory in which the U.S. suffered two major defeats before President Washington dispatched a newly trained army to the region, which decisively defeated the Indian confederacy in 1794.

"We have met the enemy and they are ours." Commodore in the , 1813. (Painting by William H. Powell, 1865)
"We have met the enemy and they are ours." Commodore Oliver Hazard Perry in the Battle of Lake Erie, 1813. (Painting by William H. Powell, 1865)

When revolutionary France declared war on Great Britain in 1793, the United States sought to remain neutral, but the Jay Treaty, which was favorable to Great Britain, led to a "Quasi-War" at sea with France from 1798 to 1801. George Washington was called out of retirement to head a "provisional army" in case of invasion by France, but President John Adams managed to negotiate a truce.

Later, in 1801, the United States and Tripoli fought the First Barbary War.

When Great Britain and France went to war again in 1803 with renewed vigor, the United States sought to remain neutral while pursuing overseas trade. This proved difficult, and the United States finally declared war on Great Britain—the War of 1812. Not hopeful of defeating the Royal Navy at sea, the U.S. attacked the Empire by invading Canada. This invasion dovetailed with an ongoing pan-tribal frontier resistance headed by the Native American leader Tecumseh. Although the War of 1812 ended as a stalemate between the United States and Great Britain in 1815, the frontier war essentially continued into 1818 with the First Seminole War.

After the War of 1812 came the Second Barbary War (1815), the Seminole Wars, the Black Hawk War, and the era of Indian Removal.

Westward expansion (1820–1860)

With the independence of the United States established, military efforts then focused on ensuring a dominant role on the continent, an idea which came to be known as "Manifest Destiny."

The Mexican-American War was a war fought between the United States and Mexico between 1846 and 1848. The war grew out of unresolved conflicts between Mexico and Texas. After having won its independence from Mexico in 1836, the Republic of Texas was annexed by the United States in 1845; however, the southern and western borders of Texas remained disputed during the Republic's lifetime.

During this time, the California Republic (also called the "Bear Flag Republic"), like the Republic of Texas, was created as the byproduct of increasing tensions between the United States and Mexico. California Republic began on June 10, 1846 when John C. Frémont and his men in Sonoma declared independence from Mexico. The rebellion itself started on June 14.

American Civil War (1861–1865)

Dead soldiers lie where they fell at , the bloodiest day in American history. issued the after this battle.
Dead soldiers lie where they fell at Antietam, the bloodiest day in American history. Abraham Lincoln issued the Emancipation Proclamation after this battle.

Sectional tensions had long existed between the states located north of the Mason-Dixon Line and those south of it, primarily centered on the "peculiar institution" of slavery and the ability of states to overrule the decisions of the national government. During the 1840s and 1850s, conflicts between the two sides became progressively more violent. Beginning with South Carolina in late 1860, states in the South seceded from the United States. On April 12 1861, forces of the South (known as the Confederate States of America or simply the Confederacy) opened fire on Fort Sumter, whose garrison was loyal to the forces of the North (who represented the United States or simply the Union).

The American Civil War caught both sides unprepared. Both the Union and the Confederacy had to build their armies practically from scratch. Following the first real engagement, it became apparently clear that the war would last much longer than a few months. It would become a war for mere existence, and the vast resources of America would be consumed before it would be resolved. The American Civil War is sometimes called the "first modern war" due to the use of mass conscription, military railroads, trench warfare, submarines and ironclads. It introduced the modern world to the horrors of total war.

Post-Civil War era (1866–1916)

The scope of the Civil War was as great as many of those in Europe, and the United States began to see itself as potential player on the world stage. With the country now stretching to the Pacific, eyes turned to overseas. The motivation behind the Spanish-American War and US involvement in the Boxer Rebellion are debated among historians.

Indian Wars (1866–1890)

After the Civil War, work began in earnest on the Transcontinental Railroad, linking California with the eastern states. Many Native American tribes of the Great Plains resisted this encroachment. Generals from the Civil War such as William Tecumseh Sherman and Philip Sheridan were assigned to conquer any Indians who offered military resistance to the building of the railroad and the expansion of the United States.

Spanish-American War

The Spanish-American War took place in 1898, and resulted in the United States of America gaining control over the former Spanish colonies in the Caribbean and Pacific, most notably Puerto Rico, Cuba and the Philippines.

Philippine-American War

US soldiers of the First Nebraska volunteers, company B, near Manila, 1899
US soldiers of the First Nebraska volunteers, company B, near Manila, 1899

The Philippine-American War was between the armed forces of the United States and the Philippines from 1899 through 1913.

This conflict is also known as the "Philippine Insurrection." This name was historically the most commonly used in the U.S., but Filipinos and an increasing number of American historians refer to these hostilities as the "Philippine-American War," and in 1999 the U.S. Library of Congress reclassified its references to use this term.

The Boxer Rebellion

The Boxer Rebellion was an uprising against Western commercial and political influence in China during the final years of the 19th century. The US contributed army and marine units, the China Relief Expedition, to an international joint force which captured Peking and forced a Chinese capitulation. By August 1900, over 230 foreigners, thousands of Chinese Christians and unknown numbers of rebels, their sympathisers and other Chinese had been killed in the revolt and its suppression.

First World War (1917–1918)

Previously isolationist, the United States became involved in Europe during the First World War, a world conflict occurring from 1914 to 1918. No previous conflict had mobilized so many soldiers or involved so many in the field of battle. Never before had casualties been so high. Chemical weapons were used for the first time, the first mass bombardment of civilians from the sky was executed, and some of the century's first large-scale civilian massacres took place. Four dynasties, the Habsburgs, the Romanovs, the Ottomans and the Hohenzollerns, who had roots of power back to the days of the Crusades, all fell after the war.

Between the wars (1919–1940)

Russian Revolution

The so-called Polar Bear Expedition was the involvement of U.S. troops, during the tail end of World War I and the Russian Revolution, in fighting the "Bolsheviks" in Arkhangelsk, Russia in 1918 and 1919, despite having been sent there on the pretext of halting a German advance on the eastern front of the war. American volunteers also participated on the Polish side in the Polish-Soviet War, forming a core of the elite fighter unit, the Kościuszko Squadron.

Spanish Civil War

The Abraham Lincoln Brigade was an organization of United States volunteers supporting or fighting for the anti-fascist Spanish Republican forces in the Spanish Civil War as part of the International Brigade.

The name "brigade" is something of a misnomer, as there were several American battalions organized under the Fifteenth International Brigade of the Spanish Republican army . This brigade was loosely organized by the Comintern and was made up of volunteers from nations around the globe.

Most of the people making up the Abraham Lincoln Brigade were official members of the Communist Party USA or affiliated with other socialist organizations. The IWW, or "Wobblies", were lightly represented. However, the brigade was made up of volunteers from all walks of American life, and from all socio-economic classes. It was the first unit of soldiers made up of Americans to have an African-American officer, Oliver Law, lead white soldiers.

Second World War (1941–1945)

During the interwar period it again reduced its military, but mobilized to its largest levels for the ensuing Second World War. The global conflict that started in 1937 or in 1939 and fought until 1945, involving the majority of the world's states and every continent except Antarctica. It was the most extensive and costly armed conflict in the history of the world.

Attributed in varying degrees to the Treaty of Versailles, the Great Depression, nationalism, and militarism, the causes of the war are a matter of debate. On which date the war began is also debated, cited as either the German invasion of Poland on 1 September 1939, the Japanese invasion of China on 7 July 1937 (the start of the Second Sino-Japanese War), or earlier yet the 1931 Japanese invasion of Manchuria. Still others argue that the two world wars are one conflict separated only by a "ceasefire".

Fighting occurred across the Atlantic Ocean, in Western and Eastern Europe, in North Africa, the Middle East, and the Mediterranean Sea, in the Pacific and Oceania, and much of East Asia and South East Asia. In Europe, the war ended with the surrender of Germany on 8 May 1945 (V-E and Victory Days), but continued in Asia until Japan surrendered on 2 September 1945 (V-J Day).

Approximately 57 million people died as a result of the war, including acts of genocide such as the Holocaust. As a case of total war, it involved the "home front" and bombing of civilians to a new degree. Nuclear weapons, jet aircraft, electrical digital computers, and radar are only a few of many war-time inventions.

Following the Second World War the United States and United Kingdom developed an increasingly strong defence and intelligence relationship. Manifestations of this include extensive basing of U.S. forces in the U.K., shared intelligence, shared military technology (e.g. nuclear technology), shared procurement (mainly British purchases of American weapon systems). See: Special relationship.

Cold War (1946–1991)

Following the WWII, the United States emerged as a global superpower vis-a-vis the Soviet Union in the Cold War. In this period of some forty years, the United States provided foreign military aid and direct involvement in proxy wars against the Soviet Union. It was the principal foreign actor in the Korean War and Vietnam War during this era. Nuclear weapons were held in ready by the United States under a concept of mutually assured destruction with the Soviet Union.

Postwar Military Reorganization (1947)

The National Security Act of 1947, meeting the need for a military reorganization to complement the U.S. superpower role, combined and replaced the former Department of the Navy and War Department with a single cabinet-level Department of Defense. The act also created the National Security Council and the CIA.

Korean War

The Korean War was a conflict between North Korea and South Korea. It was also a Cold War proxy war between the United States and its United Nations allies and the communist powers of the People's Republic of China and the Soviet Union (also a UN member nation). The principal combatants were North and South Korea. Principal allies of South Korea included the United States, Canada, Australia, the United Kingdom, although many other nations sent troops under the aegis of the United Nations. Allies of North Korea included the People's Republic of China, which supplied military forces, and the Soviet Union, which supplied combat advisors and aircraft pilots, as well as arms, for the Chinese and North Korean troops. In the United States, the conflict was termed a police action under the aegis of the United Nations rather than a war, largely in order to remove the necessity of a Congressional declaration of war.

Vietnam War

The Vietnam War was one of the longest military conflicts in U.S. history.
The Vietnam War was one of the longest military conflicts in U.S. history.

The Vietnam War was a war fought between 1957 and 1975 on the ground in South Vietnam and bordering areas of Cambodia and Laos (see Secret War) and in the strategic bombing (see Operation Rolling Thunder) of North Vietnam. In Vietnam, the conflict is known as the "American War."

Fighting on one side was a coalition of forces including the Republic of Vietnam (South Vietnam or the "RVN"), the United States, South Korea, Thailand, Australia, New Zealand, and the Philippines. Participation by the South Korean military was financed by the United States, but Australia and New Zealand fully funded their own involvement. Other countries normally allied with the United States in the Cold War, including the United Kingdom and Canada, refused to participate in the coalition, although a few of their citizens volunteered to join the US forces.

Tehran hostage rescue

Following the Iranian revolution and the resulting Iran hostage crisis a military operation named Eagle Claw attempted to rescue the hostages using a combination of special forces and helicopter evacuation, but the rescue failed with the destruction of several aircraft in an accident in the Iranian desert. The failure was attributed to inappropriate equipment, incomplete and unrealistic planning, and the lack of joint service training. Despite its size, the mission had significant effects on U.S. military doctrine and training.


Alarmed by a violent power struggle in Grenada within a leftist junta sympathetic to Cuba, the U.S. dispatched hundreds of marines, Rangers, and special forces to the island in Operation Urgent Fury. Ostensibly a mission to rescue U.S. citizens, mainly medical students, the invasion force quickly moved to seize the entire island, eventually taking hundreds of military and civilian prisoners from a variety of East Bloc nations.


In 1983 fighting between Palestinian refugees and Lebanese factions reignited that nation's long-running civil war. A UN agreement brought an international force of peacekeepers to occupy Beirut and guarantee security. The US stationed marines in an urban compound including a multi-story dormitory, once a hotel; a terrorist bombing destroyed the building, killing 241 marines. Subsequently the US Navy engaged in bombing of militia positions inside Lebanon proper.


Operation Just Cause was a 1989 invasion of Panama, mainly from U.S. bases within the former Canal Zone, to oust dictator Manuel Noriega, whose government was becoming a narco-state. The U.S. did not wish to turn over control to Noriega of the Panama Canal, which it was obligated to do under treaty, due to the canal's strategic importance.

Post-Cold War era (1992–present)

Following the end of the Cold War, the United States armed forces fought numerous limited wars as a self-envisioned constabulatory force. It began a "global war on terrorism" after the September 11, 2001 attacks.

Gulf War

The Persian Gulf War was a conflict between Iraq and a coalition force of 34 nations led by the United States. The lead up to the war began with the Iraqi invasion of Kuwait in August 1990 which was met with immediate economic sanctions by the United Nations against Iraq. Hostilities commenced in January 1991, resulting in a decisive victory for the coalition forces, which drove Iraqi forces out of Kuwait with minimal coalition deaths. The main battles were aerial and ground combat within Iraq, Kuwait and bordering areas of Saudi Arabia. The war did not expand outside of the immediate Iraq/Kuwait/Saudi border region, although Iraq fired missiles on Israeli cities.

Following the Gulf War, in order to protect minority populations, the U.S., Britain, and France maintained no-fly zones in northern and southern Iraq, which the Iraqi military frequently tested. The no-fly zones persisted until the 2003 invasion of Iraq.

Additionally, following the discovery of an aborted assassination plot aimed at former President George H.W. Bush, Navy ships bombed Iraqi intelligence facilities with cruise missiles in June 1993.


U.S. troops participated in a U.N. peacekeeping mission in Somalia beginning in 1992. By 1993 the U.S. troops were augmented with Rangers and special forces with the aim of capturing warlord Mohamed Farrah Aidid, whose forces had massacred peacekeepers from Pakistan. During a failed attempt at capturing Aidid, U.S. troops became trapped overnight by a general uprising in the Battle of Mogadishu. Though just 19 Americans died, the incident had a profound effect on U.S. thinking about peacekeeping and intervention.

War on Terrorism

The War on terrorism is a global effort by the governments of several countries (primarily the United States and its principal allies) to neutralize international groups it deems as "terrorist" (primarily radical Islamist terrorist groups, including al-Qaida) and insure "rogue nations" no longer support terrorist activities. It has been adopted as a consequence of the September 11, 2001 attacks on the United States.

The invasion of Afghanistan in order to depose that country's Taliban government and destroy training camps associated with al-Qaida is understood to have been the opening, and in many ways defining, campaign of the broader war on terrorism. The emphasis on special forces, political negotiation with autonomous military units, and the use of proxy militaries marked a significant change from prior U.S. military approaches.

Most recently, the current war in Iraq has been tied to the "War on terrorism" by the Bush administration, which has stated that Saddam Hussein of Iraq was giving safe haven to and supporting terrorist groups.

Iraq War

After the lengthy Iraq disarmament crisis culminated with an American demand that Iraqi President Saddam Hussein leave Iraq, which was refused, a coalition led by the United States and Great Britain fought the Iraqi army in the 2003 invasion of Iraq. Approximately 250,000 United States troops, with support from 45,000 British, 2,000 Australian and 200 Polish combat forces, entered Iraq primarily through their staging area in Kuwait. (Turkey had refused to permit its territory to be used for an invasion from the north.) Coalition forces also supported Iraqi Kurdish militia , estimated to number upwards of 50,000. After approximately three weeks of fighting, Hussein and the Ba'ath Party were forcibly removed, followed by an extended period of military occupation while civil government was re-established (see Post-invasion Iraq, 2003-2005). As of 2005, U.S. forces are expected to remain in Iraq for months if not years.

See also

Related lists


  • Atlas of American Military History, Stuart Murray (2005) ISBN 0816055785
  • American Military History: 1775-1902, Ed. Maurice Matloff (1996) ISBN 0938289705
  • American Military History and the Evolution of Western Warfare, Robert Doughty (1996) ISBN 0669416835
  • The American Way of War: A History of United States Military Strategy and Policy, Russell Frank Weigley (1977) ISBN 025328029X
  • A Handbook of American Military History: From the Revolutionary War to the Present, Ed. Jerry K. Sweeney and Kevin B. Byrne (1997) ISBN 0813328713
  • The Oxford Companion to American Military History, Ed. John Whiteclay II Chambers, Fred Anderson, Lynn Eden, Joseph T. Glatthaar, Ronald H. Spector, and G. Kurt Piehler (2000) ISBN 0195071980

External links

Last updated: 05-16-2005 21:35:41