The shooter’s mother is a gun nut. She moved them both to Oregon specifically for the lax gun laws. She was hoarding weapons because Obama was coming to take away her freedoms.
Oregon Shooter’s Mom Talked About Family’s Arsenal Of Guns
Oregon shooter’s paranoid mum 'kept firearm STOCKPILE in case US tightened gun laws’
This was a gun-culture family and a gun-culture massacre.
And California successfully expelled this hazard from itself by being inhospitable to it.