What people are looking for is the manifesto or the “ah-ha!” moment. Columbine had plenty of this, as have many other spree killings. Even the tower shooter in Texas was discovered to have a brain tumor.

What people are looking for is a reason that separates him from the rest of us. The box they can check to safely file him away as being a schizo, abuser, or something worse and then snapping.

What they won’t get is the reason. The Vegas shooter was deep in his own mind and seems to have not shared these things with anyone. His life on paper seems kind of grim, but nothing in the way of committing a massive shooting.