Conscription in the United States

Conscription in the United States, commonly known as the draft, has been employed by the federal government of the United States in four conflicts: the American Civil War; World War I; World War II; and the Cold War (including both the Korean and Vietnam Wars). The third incarnation of the draft came into being in 1940 through the Selective Training and Service Act. It was the country's first peacetime draft. From 1940 until 1973, during both peacetime and periods of conflict, men were drafted to fill vacancies in the United States Armed Forces that could not be filled through voluntary means. The draft was ended when the United States Armed Forces moved to an all-volunteer military force. However, the Selective Service System remains in place as a contingency plan; All male civilians between the ages of 18 and 25 are required to register so that a draft can be readily resumed if needed.

In colonial times, the Thirteen Colonies used a militia system for defense. Colonial militia laws—and after independence those of the United States and the various states—required able-bodied males to enroll in the militia, to undergo a minimum of military training, and to serve for limited periods of time in war or emergency. This earliest form of conscription involved selective drafts of militiamen for service in particular campaigns. Following this system in its essentials, the Continental Congress in 1778 recommended that the states draft men from their militias for one year's service in the Continental army; this first national conscription was irregularly applied and failed to fill the Continental ranks.

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