Of course, John Edwards was 18 years old in 1971 and unmarried - the exact profile of the type of guy the Army was looking for - but it was OK for him to get a college deferment. Little Johnny didn't volunteer, but it was A-OK.
He must have had a high draft number. I was 18 and starting my freshmen year of college in 1971 and I was drafted my first week of school. College deferments had ended by then.
Of course, he could have volunteered.