The draft in the US has been employed by the federal government in four major military 'conflicts': US Civil War; World War I; World War II; and the Cold War. The third incarnation of the draft came into being in 1940 through the Selective Training and Service Act. It was the country's first draft during peacetime. From 1940 until 1973, during both peacetime and periods of conflict, when voluntary means was not enough, men were drafted to fill the vacancies in the armed forces.

Richard Nixon was the first one to promise to end the draft during his presidential election. The draft was ended when the United States military moved to an all-volunteer military force in 1973.

However, the Selective Service System remains in place as a contingency plan; all the active male US residents between the ages of 18 and 25 are required to register so that a draft can be readily resumed if needed. If a person doesn't register, he will not be eligible for federal financial aid and may be permanently disqualified from getting any federal job, even after turning 26.

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