The Selective Service Act of 1948, passed in June of that year, created a separate new system that understayed the modern system.  All men aged 18 and over had to register with Selective Service. All men between the ages of 18 and 25 could be confiscated for a 21-month duty of service. This resulted in a 12 consecutive month of active service or 36 consecutive months of on-reserve service, with a mandatory service period of at least five years. Conscripts could be volunteered for a four-year term for military service in the regular U.S. Army or for reserves organized for a six-year term. Due to the deep budget cuts of the post-war period, only 100,000 conscripts were elected in 1948. In 1950, the number of conscripts was greatly increased to meet the requirements of the Korean War (1950-1953). Mandatory military service was first introduced in the United States during the American Civil War (1861-1865).
However, it was customary for wealthy men to hire substitutes to carry out their duties. In addition to compulsory military service, the Union has sought troops by offering cash bonuses for inclusion in the bonus system. Substitution and tempting summons have led to widespread abuses, and the Bounty Jumpers have been a persistent burden on the North`s workforce and finances. Support for compulsory military service was far from universal in the north, and public resistance culminated in the Draft Riot of 1863, a four-day, race-laden battle in which white rioters attacked federal buildings and African-American workers on the streets of New York. The project was suspended with the end of the war in 1865, and it would not return for more than half a century. The Selective Training and Service Act expired in March 1947, but Pres. Harry S. Truman, who said the Peace Army could not attract the numbers it needed to meet its global commitments, insisted that the project be extended. Congress moved on and the Selective Service Act was passed in June 1948. A flood of volunteers led the selective service system to unofficially suspend the law in early 1949 with a « design leave. » The law was due to expire in June 1950, but the outbreak of the Korean War this month led Congress to extend it for another year.