I've seen the military help young men, and I've seen it ruin some, and no, I'm not talking about war.
I have seen some come out ruined, but most of them ruined themselves (IMO)..Things like addictions, alcoholism etc , are their own choices.
I do suppose if a recruit is in a weak psychological state, they could cave under the training routine harassment ..That I must admit could happen.
.but it seems that would be temporary and transitory.. and is only the result of a problem being brought in..
War has of course, ruined some....with PTSD..and my heart goes out to them..