I think that violence is almost always a manifestation of someone's reaction to feelings of powerlessness...or their fear of losing their power, their fear of loss of control over some situation, or their feeling that they are unable to control something or someone that causes them fear and emotional pain. I was in an almost constant state of fear when I was at school (fear of certain of the other students)...but I don't tend to react violently unless I am completely and utterly desperate, with my back against the wall, and usually only if someone else is being violent to me first. I react instead by withdrawing as much as possible from people. I try to disappear.

I recall that my own father always tended to get violent (with me) (or with our various dogs) when he felt that he wasn't 100% in control of the situation. (in other words, I wasn't doing or saying what he wanted at the time...or the dog wasn't...whichever)

There was never a need for any such violence, but he could not stand not being in control. No one likes losing their power. Some react violently, some don't.