Asbergers. My brother may have had it. Ivy league graduate.
I’ve got it and I don’t shoot people.
But Aspies tend to get all worked up, especially when engaged in an echo chamber. He may have thought assassinating Trump would make him a hero in his echo chamber. He would not see it as necessarily wrong because the ends justifies the means.
Most of the mass shootings involve a perp who destroyed his hard drive. That was probably to hide the location of the echo chamber.