Well said trisher, all the points you make are valid. In the past, many children with what we would now recognise as emotional/psychological/psychiatric difficulties were excluded from mainstream. They were sent to huge 'special' boarding schools, where abuse was rife in all its form. Many progressed to special hospitals.
We now have a more well informed and enlightened approach Unfortunately, the money 'saved' when the huge special hospitals and boarding schools were closed down wasn't invested supporting young people or children who were to find inclusion beyond them and end up excluded and put into pupil referral units, or worse, given no educational provision at all. They're the young people most likely to end up in hmp, illiterate, innumerate.
To use the war example, I have lost count of the number of friends who now in their late 60's or 70's realise that the father they feared, who lost his temper, hit them, frightened them was probably suffering some kind of PTSD having been working and surviving on the Burma Railway for example. These were from middle class families, men who were functioning, who returned to professional employment after the war.
There are no simple solutions to complex problems. think of Primo Levy who survived concentration camps, wrote wonderful, life affirming books like If This is Man - who seemed to be managing his awful experiences and living well. He committed suicide in his 80's unable to tolerate his memories.