If a group of people attack another group of people, I imagine that they are all men and that they have made the decision to attack their fellow people.
We are easily irritated and are sick with fear. In many cases, I doubt that we know why we attack people. In most cases we want some resources, especially (related to) food, and we see no way to negotiate with the other group or to steal from them.
If we forget for a moment about skin color, religion, language and food, there remain some men prepared to fight. Let's strip them of weapons, clothes and dyes! Let's say we see one group coming from our left side and the other coming from our right side. Let's say that they don't start laughing (maybe because they're not hypocritical white people, but natural black people). They would have to fight as yellow people do: bare-handed. We would hear men grunting and bones breaking, and also see some blood. The two groups will mix. If these groups are quite large, the men will soon not know anymore whom to attack. Some of them will attack at random. What happens when many hundreds of men are naked, sweaty, bruised or dusty, tired and don't know their enemy because they all look the same and talk the same language?
I think: They take a rest, attend the injured, bury the dead and reconsider the war.