Why War?

H. W. Brands, a historian, often asks his classes, "Why does war exist? Nearly everyone is against war."

Brands suggests partial answers. One reason war exists is that civil relationships can't resolve all disagreements. Our founders believed that slavery would wither away, and it did wither in the North. But not in the South. It took a war to end American slavery.

Another answer is that war simplifies complex issues. That is a comfort. And in a war the ends can sometimes justify the means--to a degree, war liberates fighters from morality. We firebombed Tokyo and incinerated 100,000 civilians. 

Maybe there is something more basic. We are a branch of the chimpanzee family, sharing about 98% of our DNA. Studies show (some disagree) that chimpanzee groups are naturally violent within the group and against other groups. Chimps and humans are the only mammalian species known to attack each other in well-organized onslaughts. Or so some (but not all) experts say.