Human anger and violence long predates autos and their ills. I think it has something to do with the way our separate brains communicate, the idea that somewhere between lizard brain and the more evolved human brain there are some glitches. The latest brain, the really smart one capable of thinking up all these incredible ways of bashing others of the species, should be smart enough to know there's no end to it, once started...like the centuries old tribal feuds. But that's where the lizard brain takes over...sees things very elementally...kill or be killed, bash or be bashed. And once the evolved brain has thought up a catapault...of course the lizard brain is going to use it. And certainly fear is one of those blind triggers that gets the lizard brain going.