Sacrifice is the root of war.

Primitive people have two puzzles: death (which leads to the concept of soul) and life (female and reproductive worship), which leads to the sacrifice of ancestors. Sacrifice atoms and fears, and gain forgiveness and guidance by sacrificing balloons. Later (including Shang Dynasty in China), divination was formed. Sacrificial personnel become the link between god and people and have authority.

Different sacrifices lead to different beliefs (and vice versa). Because of blasphemy against God, punishment broke out, which can be understood as the most primitive war is the war of faith. In fact, the struggle between human beings existed before the formation of human beings, out of territorial competition for food and spouses. But this kind of struggle is individual, and the struggle between nations is mainly territorial struggle. Then there is the struggle of faith.

Even now, the cause of war is caused by resources, and the only one who really believes in war is the Crusades in the Middle Ages. There are not many religious wars, but many ethnic wars, and the conflict between resources and territory is the most common. The wars after the founding of New China are all territorial wars, and only the Korean War involves ideology.