Just How Did the Draft ,i.e. Selective Service, Work

It has been many years since the Vietnam War, wait was war ever declared? At any rate it is useful to clarify just what the draft was.
The Selective Training and Service Act of 1940, also known as the Burke–Wadsworth Act, Pub. L, 76-783, 54 Stat. 885, enacted September 16, 1940, was the first peacetime conscription in United States history. This Act required that men who had reached their 21st birthday but had not yet reached their 36th birthday, register with local draft boards. Later, when the U.S. entered World War II all men from their 18th birthday until the day before their 45th birthday were made subject to military service; all men from their 18th birthday until the day before their 65th birthday were required to register.

Draftees were selected by national lottery. If drafted, a man served on active duty for 12 months, and then in a reserve component for 10 years or until he reached the age of 45, whichever came first. Inductees, person newly admitted to military service, had to remain in the Western Hemisphere in United States possessions or territories located in other parts of the world. The act provided that not more than 900,000 men were to be in training at any one time.

The draft began in October 1940, with the first men entering military service on November 18. By the early summer of 1941, President Franklin D. Roosevelt asked the U.S. Congress to extend the term of duty for the draftees beyond twelve months to a total of thirty months, plus any additional time that he could deem necessary for national security. On August 12, the United States House of Representatives approved the extension by a single vote.

Many of the soldiers drafted in October 1940 threatened to desert once the original twelve months of their service was up. Many of these men painted the letters "O H I O" on the walls of their barracks in protest. These letters were an acronym for "Over the hill in October", which meant that the men intended to desert upon the end of their twelve months of duty. Desertions did occur, but they were not widespread. Following the Japanese attack on Pearl Harbor, Hawaii, on December 7, 1941 millions of American men entered the United States military's ranks both by volunteering and by conscription.

After the United States entered World War II, amendments to the Selective Training and Service Act on December 20, 1941, made all men between the ages of 20 and 44 liable for military service, and required all men between the ages of 18 and 64 to register. The terminal point of service was extended to six months after the war. Another amendment signed on November 13, 1942, called the registered 18- and 19-year-olds into military service. From October 1940 until March 1947—when the wartime Selective Training and Service Act expired after extensions by Congress—over 10,000,000 men were inducted. 

Volunteers could join at age 18, 17 with parental consent. Starting in Dec 1942 the Navy and Marine Corp allowed 17 year olds to join. The army only allowed 18 year old draftees – no volunteers, within the parameters of the Acts described above.

Courtesy of Wikipedia – pls donate!