I've made my point, if you don't want to see it, okay. My point is that people are taught to mistrust people from other cultures, in many cases. They are attitudes that are instilled before a person is capable of critical thought of their own. For example if your parents are constantly mistrusting and talking shit about black people, about how they're lazy and they'll rob you, you'll grow up, most likely, feeling the same way. And as such, you will believe that the way you feel is correct, and you'll be afraid of them which leads to anger and eventually hatred, because you'll believe they're out to get you, that they hate you. That's just an example, but it happens all over the world. It isn't always skin color either, sometimes it's two tribes that live in close promixity of the same color (Tutsis and Hutus in Rwanda is a relatively recent example that led to genocide - you think all those people were evil people? You don't think that if the way generations of people were raised with regards to how they viewed these "others" had been different, those people wouldn't have committed genocide?). My point is, peoples' motivations for committing atrocities are very rarely "evil". They have their reasons and they feel justified. The people leading these atrocities are using social programming to get everyone else to follow. That's what happened in Germany in WW2. Do you expect me to believe that you honestly think every German who was in the military who contributed to the Holocaust was an evil person?
What about other wars? is every soldier who kills another person in a war evil? Killing is evil, right? By your argument, the reason shouldn't matter, it makes them evil regardless.
I'm saying these acts are evil acts, but the people who commit them are more complex than that. Most people believe they have the moral high ground most of the time. And what I'm really trying to say with these examples is that racism is absolutely a thing, it is not some excuse or fabrication as you are suggesting. It, along with many other "isms", are often the reason that people feel justified to commit evil acts, and that without these ideologies, the same people would not commit those acts. I'm not absolving personal responsibility, though I can see why you would assume I am. I am saying, however, that if we can be aware of what harm these destructive ideologies cause, maybe we can be self-aware enough as a species to overcome them and stop being horrible to each other.* But if we deny their very existence, well, we're not likely to make any progress, are we?
*And there will, of course, always be sociopaths/psychopaths in existence who seek to hurt others regardless, because it is their nature. But this is not the vast majority of people. Most people are led to atrocities in the name of something that they inherited from their parents/culture, believing it is their right or even their moral duty to do so.
**I apologize for suggesting you were trolling, that doesn't really help anything and I should give you the benefit of the doubt. It's just hard for me to fathom your position that racism is a fabrication.