At their age, most of this lies at the parents feet. They raised them, why did they raise people with such little regard for others?
In my opinion they raised them to have no regard for themselves. I believe the Spanish teacher was most likely a substitute for the parents either by doing to them what the parents did, or breaking the rules they imagine their parents taught as sacred. The pain that we suffer is conflict, a self division or inner split. We were taught to hate evil by exposure to the hate of evil we were told was within us.
This creates a love contempt relationship, or Stockholm Syndrome. Our respect for authority is created by fear and for some the force of the lessons create inner conflict we can’t contain. A percentage of us snap either because we had it particularly bad, experience horrific events later in life or both, in my opinion.
All of this is made worse by fear, the fear of pain, the fear of reliving consciously what we went through as children.
Children have no ego and thus no armor to shield themselves from threat. Once we could experience pain to our full capacity, to the maximum we can experience it. Children can’t survive continual conscience awareness of that. We shut down and submit, conform and tell ourselves we are thus worthy of love. The problem is that at the deepest levels we do not consciously remember, we don’t believe it.
That is the task we face, in my opinion, if we want to end the cycle of violence we pass down to our children. We do not know ourselves.