" Perhaps we should rejoice that people’s emotions aren’t designed for the good of the group. Often the best way to benefit one’s group is to displace, subjugate, or annihilate the group next door. Ants in a colony are closely related, and each is a paragon of unselfishness. That’s why ants are one of the few kinds of animal that wage war and take slaves. When human leaders have manipulated or coerced people into submerging their interests into the group’s, the outcomes are some of the history’s worst atrocities. "

― Steven Pinker , How the Mind Works