Walt, being young and foolish and heavily influenced by MASH, I tried to get into Medical Service Corps or M.I. The Exec at our ROTC detachment told me I was getting Armor because I was a history major, a connection I never quite got. Maybe the idea was since Patton was a history buff all tankers should be history buffs.
Later, I found out Armor was the place to be. There's nothing quite like cruising with a lotta tons of steel wrapped around you. (Well, driving a jet fighter would be cool too, but my eyesight nixed that idea.)