There was always someone watching and waiting for you to screw up. No news, censored mail. Well after all, they want you to die for God, country, and the guy next to you. Perhaps it's not an exact analogue, but it is a very similar model of behavior modification to the ones practiced by cults. Thankfully, however, Basic Training actually ends, unlike cult practices.
Most people snap out of the basic training mode when they get back into a more normal routine.