Evil

What makes a person evil? Is it just horrible luck, is it a personality flaw, a genetic disorder, that makes a person turn to hate? What would make a person target all their anger on another culture? I like to think that given the right circumstances, everyone would choose peace. But would they really? I mean, some people go through hell, and they are stronger for it. Others seem to have no hardship at all, and only an accident of birth gives them fuel for their hatred. Would bin Laden, or Hitler, or any other evil person in history, would they have been different if circumstances had been different? Or were their circumstances only an excuse, so that they would have been evil no matter what their life was like? I find it hard to believe that people can hate other humans so easily, without questioning whether their "crime" might be simply their existence. As glad as I am to be human, I often envy other, less intelligent species, that don't understand the concepts of hate, or prejudice, or evil. Their lives must be so much simpler.