The Continental Army was created on 14 June 1775 by the Continental Congress as a unified army for the states to fight Great Britain, with George Washington appointed as its commander.[1The Army was initially led by men who had served in the British Army or colonial militias and who brought much of British military heritage with them. As the Revolutionary war progressed, French aid, resources, and military thinking influenced the new army, while Prussian assistance and instructors, such as Friedrich Wilhelm von Steuben, had a strong influence.
George Washington used the Fabian strategy and used hit-and-run tactics, hitting where the enemy was weakest, to wear down the British forces and their Hessian mercenary allies. Washington led victories against the British at Trenton and Princeton, and then turned south. With a decisive victory at Yorktown, and the help of the French, the Spanish and the Dutch, the Continental Army prevailed against the British, and with the Treaty of Paris, the independence of the United States was acknowledged.
After the war, though, the Continental Army was quickly disbanded as part of the American distrust of standing armies, and irregular state militias became the new nation's sole ground army, with the exception of a regiment to guard the Western Frontier and one battery of artillery guarding West Point's arsenal. However, because of continuing conflict with Native Americans, it was soon realized that it was necessary to field a trained standing army. The first of these, the Legion of the United States, was established in 1791.
The War of 1812 (1812–1815), the second and last American war against the British, was less successful than the Revolution had been. An invasion of Canada failed, and U.S. troops were unable to stop the British from burning the new capital of Washington, D.C.. However, the Regular Army, under Generals Winfield Scott and Jacob Brown, proved they were professional and capable of defeating a British army in the Niagara campaign of 1814. Two weeks after a treaty was signed, though, Andrew Jackson defeated the British invasion of New Orleans. However this had little effect, as per the treaty both sides returned to the status quo.
Between 1815 and 1860, a spirit of Manifest Destiny was common in the U.S., and as settlers moved west the U.S. Army engaged in a long series of skirmishes and battles with Native Americans that the colonists uprooted. The U.S. Army also fought the short Mexican–American War, which was a victory for the United States and resulted in territory which became all or parts of the states of California, Nevada, Utah, Colorado, Arizona, Wyoming and New Mexico.
The Civil War (1861–1865) was the most costly war for the U.S. After most states in the South seceded to form the Confederate States of America, CSA troops opened fire on the Union-held Fort Sumter in Charleston, South Carolina, starting the war. For the first two years Confederate forces solidly defeated the U.S. Army, but after the decisive battles of Gettysburg in the east and Vicksburg in the west, combined with superior industrial might and numbers, Union troops fought a brutal campaign through Confederate territory and the war ended with a Confederate surrender at Appomatox Courthouse in April 1865. Based on 1860 census figures, 8% of all white males aged 13 to 43 died in the war, including 6% in the North and 18% in the South.
Following the Civil War, the U.S. Army fought a long battle with Native Americans, who resisted U.S. expansion into the center of the continent. But by the 1890s the U.S. saw itself as a potential international player. U.S. victories in the Spanish-American War (1898) and the controversial and less well known Philippine-American War (1898–1913), as well as U.S. intervention in Latin America and the Boxer Rebellion, gained America more land.
In 1910 US Signals Corps acquired and flew US Army's first aircraft, the Wright Type A biplane. The United States joined World War I (1914–1918) in 1917 on the side of Russia, Britain and France. U.S. troops were sent to the front and were involved in the push that finally broke through the German lines. With the armistice on 11 November 1918, the Army once again decreased its forces.
The U.S. joined World War II after the Japanese attack on Pearl Harbor on 7 December 1941. On the European front, U.S. Army troops formed a significant portion of the forces that captured North Africa and Sicily. On D-Day and in the subsequent liberation of Europe and defeat of Germany, millions of U.S. Army troops played a central role. In the Pacific, Army soldiers participated alongside U.S. Marines in the "island hopping" campaign that wrested the Pacific Islands from Japanese control. Following the Axis surrenders in May (Germany) and August (Japan) of 1945, Army troops were deployed to Japan and Germany to occupy the two defeated nations. Two years after World War II, the Army Air Forces separated from the Army to become the United States Air Force on 18 September 1947 after decades of attempting to separate. Also, in 1948 the Army was desegregated.
However, the end of World War II set the stage for the East-West confrontation known as the Cold War (late 1940s to early 1990s). With the outbreak of the Korean War, concerns over the defense of Western Europe rose. Two corps, V and VII, were reactivated under Seventh United States Army in 1950 and American strength in Europe rose from one division to four. Hundreds of thousands of U.S. troops remained stationed in West Germany, with others in Belgium, the Netherlands and the United Kingdom, until the 1990s in anticipation of a possible Soviet attack.
During the Cold War, American troops and their allies fought Communist forces in Korea and Vietnam (see Domino Theory). The Korean War began in 1950, when the Soviets walked out of a U. N. Security meeting, removing their possible veto. Under a United Nations umbrella, hundreds of thousands of U.S. troops fought to prevent the takeover of South Korea by North Korea, and later, to invade the northern nation. After repeated advances and retreats by both sides, and the Peoples' Republic of China 's entry into the war, a cease-fire returned the peninsula to the status quo in 1953.
The Vietnam War is often regarded as a low point in the Army's record due to the use of drafted personnel, the unpopularity of the war with the American public, and frustrating restrictions placed on the Army by US political leaders (i.e. no invading communist held North Vietnam). While American forces had been stationed in the Republic of Vietnam since 1959, in intelligence & advising/training roles, they did not deploy in large numbers until 1965, after the Gulf of Tonkin Incident. American forces effectively established and maintained control of the "traditional" battlefield, however they struggled to counter the guerrilla hit and run tactics of the communist Viet Cong and the North Vietnamese Army. On a tactical level, American soldiers (and the US military as a whole) never lost a sizable battle. For instance in the Tet Offensive in 1968, the US Army turned a large scale attack by communist forces into a massive defeat of the Viet Cong on the battlefield (though at the time the offensive sapped the political will of the American public) which permanently weakened the guerrilla force; thereafter, most large scale engagements were fought with the regular North Vietnamese Army. In 1973 domestic political opposition to the war finally forced a US withdrawal. In 1975, Vietnam was unified under a communist government.
The Total Force Policy was adopted by Chief of Staff of the Army General Creighton Abrams in the aftermath of the Vietnam War and involves treating the three components of the Army – the Regular Army, the Army National Guard and the Army Reserve as a single force. Believing that no US president should be able to take the United States (and more specifically the US Army) to war without the support of the American people, General Abrams intertwined the structure of the three components of the Army in such a way as to make extended operations impossible, without the involvement of both the Army National Guard and the Army Reserve.
The 1980s was mostly a decade of reorganization. The Army converted to an all-volunteer force with greater emphasis on training and technology. The Goldwater-Nichols Act of 1986 created Unified Combatant Commands bringing the Army together with the other four military under unified, geographically organized command structures. The Army also played a role in the invasions of Grenada in 1983 (Operation Urgent Fury) and Panama in 1989 (Operation Just Cause).
By 1989 Germany was nearing reunification and the Cold War was coming to a close. The Army leadership reacted by starting to plan for a reduction in strength. By November 1989 Pentagon briefers were laying out plans for 'Operation Quicksilver,' a plan to reduce Army endstrength by 23%, from 750,000 to 580,000. A number of incentives such as early retirement were used. In 1990 Iraq invaded its smaller neighbor, Kuwait, and U.S. land forces, led by the 82nd Airborne Division, quickly deployed to assure the protection of Saudi Arabia. In January 1991 Operation Desert Storm commenced, a U.S.-led coalition which deployed over 500,000 troops, the bulk of them from U.S. Army formations, to drive out Iraqi forces. The campaign ended in total victory for the Army, as Western coalition forces routed the Iraqi Army, organized along Soviet lines, in just one hundred hours.
After Desert Storm, the Army did not see major combat operations for the remainder of the 1990s. Army units did participate in a number of peacekeeping activities, such as the UN peacekeeping mission in Somalia in 1993, where the abortive Operation Gothic Serpent led to the deaths of eighteen American soldiers and the withdrawal of international forces. The Army also contributed troops to a NATO peacekeeping force in the former Yugoslavia in the middle of the decade.
After the September 11 attacks, and as part of the Global War on Terror, U.S. and NATO combined arms (i.e. Army, Navy, Air Force, Marine, Special Operations) forces invaded Afghanistan in 2001, replacing the Taliban government.
The Army took part in the combined U.S. and allied invasion of Iraq in 2003. In the following years the mission changed from conflict between regular militaries to counterinsurgency, with large numbers of suicide attacks resulting in the deaths of more than 4,000 U.S. service members (as of March 2008) and injuries to thousands more. The lack of stability in the theater of operations has led to longer deployments for Regular Army as well as Reserve and Guard troops.
The task of organizing the U.S. Army commenced in 1775. During World War I, the "National Army" was organized to fight the conflict. It was demobilized at the end of World War I, and was replaced by the Regular Army, the Organized Reserve Corps, and the State Militias. In the 1920s and 1930s, the "career" soldiers were known as the "Regular Army" with the "Enlisted Reserve Corps" and "Officer Reserve Corps" augmented to fill vacancies when needed.
In 1941, the "Army of the United States" was founded to fight World War II. The Regular Army, Army of the United States, the National Guard, and Officer/Enlisted Reserve Corps (ORC and ERC) existed simultaneously. After World War II, the ORC and ERC were combined into the United States Army Reserve. The Army of the United States was re-established for the Korean War and Vietnam War and was demobilized upon the suspension of the Draft.
Currently, the Army is divided into the Regular Army, the Army Reserve, and the Army National Guard.The Army is also divided into major branches such as Air Defense Artillery, Infantry, Aviation, Signal Corps, Corps of Engineers, and Armor. Prior to 1903 members of the National Guard were considered state soldiers unless federalized by the President. Since the Militia Act of 1903 all National Guard soldiers have held dual status: as National Guardsmen under the authority of the governor of their state and as a reserve of the U.S. Army under the authority of the President.
Since the adoption of the total force policy, in the aftermath of the Vietnam War, reserve component soldiers have taken a more active role in U.S. military operations. Reserve and Guard units took part in the Gulf War, peacekeeping in Kosovo, and the 2003 invasion of Iraq.
Various State Defense Forces also exist, sometimes known as State Militias, which are sponsored by individual state governments and serve as an auxiliary to the National Guard. Except in times of extreme national emergency, such as a mainland invasion of the United States, State Militias are operated independently from the U.S. Army and are seen as state government agencies rather than a component of the military.
Although the present-day Army exists as an all volunteer force, augmented by Reserve and National Guard forces, measures exist for emergency expansion in the event of a catastrophic occurrence, such as a large scale attack against the U.S. or the outbreak of a major global war.
The final stage of Army mobilization, known as "activation of the unorganized militia" would effectively place all able bodied males in the service of the U.S. Army. The last time an approximation of this occurred was during the American Civil War when the Confederate States of America activated the "Home Guard" in 1865, drafting all males, regardless of age or health, into the Confederate Army.