It's an interesting point. You are saying you don't think it's about politics at all?? That it was just a disease process or a completely personal issue that would have resulting in a mass shooting in 1927 or 2043, never mind politics or partisan hatreds existing in the U.S.?
It may be what he did was not at all about partisan politics, and yet the culture of hatreds and gun violence and games and movie toughness still did influence him to shoot a lot of kids rather than, I don't know, run away to Chicago. Or stick his hand in his shirt and wear a cocked hat like Napoleon the way crazies did a couple centuries ago.
Remember that crazy who shot the congresswoman in the Southwest? Hazy on the details. That kid was SO CRAZY his eyes sort of whirled around and he could hardly walk or talk. He had been getting worse and worse for months, we heard later; he lived at home and no one knew what to do with him. BUT ---- it WAS political! No matter how really impressively psychotic he was, he DID figure out where to find a congresswoman and go there, locked and loaded. So I think crimes and psychosis do take on the cultural flavor of their times. Crazies are far, far more violent now, because the country is more violent.