 After Pearl Harbor the STSA was further amended (December 19, 1941), extending the term of service to the duration of the war plus six months and requiring the registration of all men 18 to 64 years of age.During World War II, 49 million men were registered, 36 million classified, and 10 million inducted.18 and 19 year olds were made liable for induction on November 13, 1942.