As of 1973 the United States army become an all-volunteer force, but echoes of the draft still remain with the requirement of every U.S. male citizen over the age of 18 to register, and foreign national citizens, including even illegal immigrants, to register before their 25th birthday. Conscription was mandatory in the colonial era: all able-bodied males had to train and serve in the militia for a period of time. The mandatory service requirement was dropped by the Civil War, but all able-bodied males were still required to serve in wartime. With one significant change, that was the trend in WW I.

On this day, June 5, in 1917, the first draft to call up soldiers for WW I was held. Some 10 million males between the ages of 21 and 31 registered.

This time the draft was mandatory to all economic classes, as the loophole allowing “substitute” fighters was closed. In the Civil War, a clause in the draft law allowed individuals to avoid fighting if they could furnish a replacement or (until 1864) pay a commutation fine. The upper classes had no problems coming up with replacement hires or paying the fines, which resulted in very few of them fighting in the war.