"Virtually everyone" - yes -in the 60's if you had the brass the 1st thing you did when you got to the age of 18 was put your name on the list to get into the Reserves.
When I was at Uni then you used to get a 4S - a student deferrment which meant you couldnt get drafted out of school.
It then changed and then whether you were in 4th year med or law you were eligbile.
My # was #15 - gone!
