As my cousin Bolshie Bob says...
I do have a tendency to "go all Toynbee" and look for abstract social and anthropological reasons for what is going on in history. Both you and he, I'm afraid, have more of a tendency to say; "Deep down inside, the bastards are no damn good."
In either case, its really two ways of saying exactly the same thing: different subspecies of humanity tend to react in different ways to what is going on the culture. Unfortunately, they are predictable, and the end result appears to repeat itself.
Sometimes with understanding comes despair.