Where do the real monsters come from? [View All]

I really began to wonder this when Yugoslavia fell apart. People who were neighbours,often inter-married,began slaughtering each other. Now killing during a battle is going to happen. But where do the butchers come from? A war starts,and out of the woodwork comes men that can cut a prisoner's throat,and laugh about. He had never killed before,yet now he gleefully does it. I can understand revenge,but not that.
On another thread someone posted that he had seen a bumpersticker that said "Save America,shoot a liberal". As I've gotten older I recognize people who have no sympathy for others. Not one ounce of compassion. And they blame others for their problems. Are these the monsters,just waiting for their day?