Why are people evil?

Here’s a rabbit hole I went down yesterday:

• Read this article (in print, not online because I’m old school!) about Bosnian war criminals living in the U.S. and how they might be deported.
• Asked my wife, “Wait, why are we deporting people for something that happened on foreign soil 20 years ago?”
• We got into a deep discussion about that. (I agree there should be no statue of limitations on genocide, if you’re wondering about my personal morality.)
• I walked over to the dishwasher as she was going to take a shower, and I casually tossed out, “Hey, do you know why Argentina was so accepting of Nazis?”
• She didn’t really, so I Googled that.
• That led me here.
• I started reading about a bunch of terrible Nazi shit, most notably Mengele (who did escape and eventually died on a Brazilian beach).
• My wife’s still in the shower, and I’m all like, “Whoa, so what are the origins of evil?”
• Rabbit Hole №2 commenced.

I’m pretty interested in evil. I don’t think it’s weird to say that; most of the notable TV characters of the past decade are, in fact, anti-heroes. We all seem pretty fascinated with bad people at a pop culture level.