 From a pool of approximately 27 million, the draft raised 2,215,000 men for military service (in the United States, South Vietnam, and elsewhere) during the Vietnam War era.The majority of service members deployed to South Vietnam were volunteers, even though hundreds of thousands of men opted to join the Army, Air Force, Navy, and Coast Guard (for three or four year terms of enlistment) before they could be drafted, serve for two years, and have no choice over their military occupational specialty (MOS).Of the nearly 16 million men not engaged in active military service, 57% were exempted (typically because of jobs including other military service), deferred (usually for educational reasons), or disqualified (usually for physical and mental deficiencies but also for criminal records including draft violations).