There is a striking level of divisiveness in contemporary youth culture, with high schools divided into rival tribes of goths, preppies, jocks, punks and whatever else is the flavour of the week. Usually this is expressed in nothing more harmful than a mutual snobbery, but it seems that both of the recent high-school shootings were motivated by rivalries of this sort. We adults need to ask if we are teaching our youth mutual respect and acceptance of differences. Buddhism teaches that we ought to practise universal friendliness and compassion, and it is not the only religion that teaches this. We first need to accept the other, the strange one, as intrinsically like ourselves.
All beings are conscious and all know suffering.
This simple reality is more fundamental than any possible differences. Violence always arises first in the mind and it is striking how often mass violence is preceded by a dehumanization of the target group. One needs only to look at the propaganda of warring states, past and present to see countless examples of this. The first act of violence is always the radical dichotomy we experience in our own hearts when we judge another to be unlike ourselves, and unworthy of our compassion. Tribalism and territorialism are no doubt ancient human instincts, as they are expressed not alone among our primate cousins but among many of the higher mammals.