It's the warning that "Fight Club" gave us but most didn't see the connection. Fight Club was Not Fiction. These violent males blame the rest of us, not their own actions, for their existence.
Whle most mass shooters are white males with more access to better paying jobs than the rest of us, (yes still an issue in many spaces)
this specific type never accepts accountability for their situations.
It's always someone else's fault.
This trait is very near what the DSM-IV says of a person with a Sociopathic diagnosis.
Notice how the murderer mentioned in this article frequently assaulted others from a young age, but instead of addressing his issues, society gave him access to guns.
We exist in a world that places little to No regulation on access to guns, while simultaneously disregarding the obvious signs of violent tendencies in young males, "Oh he's just being a boy."
Boys play and run and jump. Boys enjoy toys and friendship.
Habitually fighting and verbally demenaing others is not what boys do. That's what a sociopath does.