That stuff has nothing to do with it. Every spree shooter since Columbine has had an identical background. IE they're Sociopaths. Sociopaths are born that way- they have no empathy.
Each one of them:
*got in trouble early for compulsive arson.
* got in trouble early for compulsive theft.
*got in trouble early for felony animal cruelty.
*got in trouble early for violent or sexual assaults against elementary school kids.
Long before they picked up a gun.
This is the same background serial killers have BTW. When I worked for the courts one Juvie probation officer brought a teen in to me for drug testing. He had that same background.
His P.O. told me, "we know he's gonna shoot up a school someday."
Before the Carter administration they used to lock these kids up for being Criminally Insane.
Carter cut funding to the states for this and bragged of "mainstreaming the mentally ill."
Most asylums closed and America suddenly had a homeless crisis and a spree shooter crisis.
It is a mental health problem, but money to fund mental health facilities is money the Uniparty Establishment crooks can't pocket.