I hesitate to put it forward. Most would probably not. It's a simple theory likely to be dismissed as simplistic ...and why should my opinion be relevant in the face of an alternate,universal conclusion?
Well you know, it doesn't have to. Any more than the rest .
How does anyone get inside the head of a dead gunman with a high-powered killing machine and a sufficient supply of ammunition to take the greatest number along with himself?
He made a phone call and declared his intention.
In the circumstance, why should that be so readily acceptable?
Why should this mass shooting be different from others over the years here and elsewhere?
Why is it different to Marc Lepine who killed fourteen women in Montreal in 1989 and wounded ten more and four men ? His name will never be forgotten which more than likely was his objective.
He was twenty-four years old. He had tried and failed in various endeavors and typically found others to blame for his problems.
His father was said to have had no respect for women and abandoned the family when the boy was seven. He struggled all his short life and ...well....we know how it ended.
His father was Algerian but Islamic or radical jihadism was not being talked about then.
Plain, common or garden variety insanity was easily identified.
No deep dark evil plot involving nations .
Just a mad person overwhelmed with life's vicissitudes and access to a weapon capable of taking dozens of lives along with his own to mark his passing.