[Drew68]

I’m leaning towards decades of suppressed anxiety boiling up towards an explosion, possibly fueled by benzo and alcohol addiction, taken, ironically, to deal with anxiety.

That's where I'm leaning as well. I think people looking for some kind of religious or political motive aren't going to find one. So far there's zero evidence this guy was ideological.

FWIW, looking at the extensive history of mass shootings in the United States, very few of them were politically or religiously motivated.

[jpsb]

So far there's zero evidence this guy was ideological.

Hmmmmm,

[Zhang Fei]

I suspect (and hope) we’ll find out more in the days ahead. He did understand one key aspect of operational security, though. Once a secret is known by more than one person, it’s no longer a secret. So maybe he took his motive to the grave with him.