From there it's a short hop to having these helmets (by then no longer optional at all) administer other kinds of signals, directly to the soldier's brains: to relay orders, identify targets... and to tell them when to pull the trigger.
But, the process of breaking down a citizen and building a solider could easily be described as developing a new operating system for the soldier, one which is designed to utilize the radio/hearing/brain pathway to achieve an identical end to your electrical end.
With "electronic helmet brain control", boot camp is irrelevant, but bootcamp and culture is itself an archaic "brain control", which serves an identical purpose already.
Don't radios with earpieces already do that?