I completely agree with you. This isn't the result of guns, or movies, or video games or one individual asshole with an evil agenda. I don't know how anybody could take such a granular view of a tragedy like this.
This is about a huge, hard to define and wholly ed up sense of dread that's coursing through our society. It's a deep-seeded sadness and fear that almost everybody is complicit in. This is a sad place and time for a lot of very scared people. Particularly American people. And I hate when the pressure gets to be too much. That's what causes incidents like this. A cultural sadness so deep and scary that it almost brainwashes and turns an otherwise normal American into someone who just can't take it anymore and who completely loses touch with reality and any shred of respect for human lives.
The victims of something like this deserve a much harder look at the root cause than some reductive, stupid, trite, 'this kid is just evil' or 'guns are just evil' or 'movies are just evil' rhetoric or agenda. It's everything and everyone; it's who we are as a people. Those in this thread who are on the defensive about a particular issue or cause, are an insult to the lives lost. And they're perpetuating the problem even as we speak.