That is my point. We are increasingly dividing ourselves (the human race) into groups, be them religious, political, national, ethnic, racial, sexual, ect. We then carry with us the baggage that these divisions bring with them (religious dogma, political ideologies, nationalistic fervor, racial & ethnic & class stereotypes, ect). They prevent us from seeing that we are all of one species, one life force. They DIVIDE us, but the differences in our DNA are negligible. Even categorizing ourselves as "humans" artificially separates ourselves from the "animals". We are all LIFE. Think about it.
These beliefs close our minds; they restrict our thinking. We are prejudiced by our beliefs and these prejudices affect the way we see things in reality. They distort reality. They give easy answers to complex or even unanswerable questions that are not rooted in actuality. This is bound to cause conflict because reality can't even be agreed upon between the groups. Beliefs are the subtle, "root" violence that leads to physical, overt violence and war.
It may be easy to say that violence is self defeating, it is much more difficult to SEE that violence (in all its forms) is self defeating.