Interesting I consider belligerence a characteristic related to a rather earlier evolutionary stage than anything... yeah, like cavemen trying to kill each other for land, food, mating and status. In other words, warfare might tell how much a civilization hasn't evolved its technology and social organization so that it still needs to use brute force to supply itself. The more a civilization is evolved, the more they perceive the warfare is nothing but a big waste of energy, resource, time and lives.