Just think of the trust that often exists in soldiers. Within their own unit, you could say they have to trust each other. A spirit of camaraderie builds up and, in the end, they will risk their lives for each other. They may even go so far as to dehumanise the other, enemy group - a mechanism you can also observe in chimps.
Jane GoodallSome people say, therefore, that violence and war are inevitable. I say rubbish: Our brains are fully capable of controlling instinctive behavior.
Jane Goodall