The most irritating thing we do whenever someone kills a bunch of people is that we immediately want the easiest answer we can find, accuracy be damned. Everyone combs through everything they can find about the person looking for one simple explanation.
Oh, he’s an atheist, that’s why he did it. Of course. Case closed.
Oh, he had mental problems, that’s why he did it. Of course. Case closed.
Oh, he was just upset about a parking space, that’s why he did it. Of course. Case closed.
Oh, he owned guns, that’s why he did it. Of course. Case closed.
Oh, he hated Muslims, that’s why he did it. Of course. Case closed.
I think we do this because the act is so horrifying and nonsensical to us that we yearn for the easiest, most obvious solution. Anything more nuanced than that is psychologically upsetting to us because it might require us to think more deeply about the situation than we want to do. We want it all wrapped up in a neat little bow, and as quickly as possible, so that we can put it away and not have to deal with it. And it might even require us to do some self-reflection or recognize something bad about our in-group, something humans almost always try to avoid.
And I use the term “we” here very intentionally. I’ve done it too. I’ll probably do it again. I bet you have, too. But it’s something we should strive to avoid. Doing so takes effort, but it’s worth it.