<P> The draft lottery had social and economic consequences because it generated resistance to military service and the resisters, draft evaders or "draft dodgers", were generally young, well - educated, healthy men . The fear of military service in Vietnam influenced many young men born in the late 1940s to join the National Guard . These young men were aware that the National Guard would be unlikely to send its soldiers to Vietnam . Many men were unable to join the National Guard, even though they had passed their physicals, because many state National Guards had long waiting lists just to enlist . Still others chose legal sanctions such as imprisonment, either showing their disapproval by burning their draft cards or draft letters, or simply not presenting themselves for the military service test . Others left the country, commonly moving to Canada . The number of American citizens who moved to Canada during the Vietnam war because of the draft is estimated to be around 125,000; it is believed that about half returned to the United States after the Nixon era (when the war was also over) (1975). </P> <P> Lottery procedure was improved the next year although public discontent continued to grow until "authority to induct expired on June 30, 1973". </P> <P> In 1970, covering 1951 birthdates for use during 1971 (sometimes called the 1971 draft), scientists at the National Bureau of Standards prepared 78 random permutations of the numbers 1 to 366 using random numbers selected from published tables . From the 78 permutations, 25 were selected at random and transcribed to calendars using 1 = January 1, 2 = January 2,...365 = December 31 . Those calendars were sealed in envelopes. 25 more permutations were selected and sealed in 25 more envelopes without transcription to calendars . The two sets of 25 envelopes were furnished to the Selective Service System . </P> <P> On June 2, an official picked two envelopes, thus one calendar and one raw permutation . The 365 birthdates (for 1951) were written down, placed in capsules, and put in a drum in the order dictated by the selected calendar . Similarly, the numbers from 1 to 365 were written down and placed into capsules in the order dictated by the raw permutation . </P>

When did the us draft for the vietnam war