In my opinion all types of wars or violance should be avoided, unless if this action is for defending your country against an external militar agression or against a government that is violating the law of the country or any similar situation. However, wars and violence is extremely difficult to be excluded from human behavior, particularly in case of massive poverty and hunger, oppression, systematic abuse of the authorities against their own population, just to mention some examples.
”So long as there are men there will be wars.” Albert Einstein
“Human existence may be simpler than we thought. There is no predestination, no unfathomed mystery of life. Demons and gods do not vie for our allegiance. Instead, we are self-made, independent, alone, and fragile, a biological species adapted to live in a biological world. What counts for long-term survival is intelligent self-understanding, based upon a greater independence of thought than that tolerated today even in our most advanced democratic societies.” Edward O. Wilson
I think wars can be avoided, if we find a better way of balancing different interests. Regarding the purpose of human existence I agree with Florian Glodeanu/Edward O. Wilson.