Carried Away by Violence
Gandhi called violence the "law of the jungle". Animals are prone to use violence instinctually. Human beings, on the other hand, have the capacity to reason, and more importantly, for Gandhi, to feel empathy. We don't have to fight because we can think in defiance of our instincts. Instead of fighting, we can come to realize with our hearts and our heads that we can cooperate and accomplish more working together than by killing each other. Thus, the progress of human civilization, Gandhi believed, was tied to more and more people realizing the benefits of nonviolence.
A new book, by sociologist Randall Collins, seems to give some foundation to these ideas (you can read a good summary here). In Violence: A Micro-sociological Theory (you can look at the first chapter here), Collins argues that human beings are actually quite reluctant to engage in physical violence. We have developed as social animals and have all sorts of cues to defuse situations. Instead of focusing on the biology of violent people, or the broad social forces that might predispose people to violence, Collins focuses on the particular situations that lead to violent outbursts.
One of the most interesting ideas to come out of this book is the idea of "forward panic". In a situation of forward panic, two people are arguing or disagreeing about something intensely, leading to a rise in tension. Then one of the persons flinches or backs down. The tension has been rising so much that the person who has not flinched is carried away by the tension and attacks.
You can see an example of "forward panic" in the now infamous Utah Highway patrol Taser incident:
It seems clear that the civillian is tasered the moment he turns away from the patrolman.
Collins suggests one of the best things to do to contain violence is to train soldiers in forward panic (and police could use this too, apparently). This way we don't automatically give in to our instincts, but learn to trust our social cues about the need to restrain tension.