Not tinfoil hat time, either.
The shooters at Columbine (Kliebold and Harris), Kip Kinkel, and a host of other school shooters (during the Clinton administration) were on some sort of psychoactive medication, often prescribed for depression. There may well be a connection.
The shooter usually wraps the spree up by killing themselves.
You're right!
I believe it's almost like a self-gratifacation. His last "F*ck You" to the world for the miserable life he lived and blames us for.
Coward.
The connection is that they were all disturbed in the first place, which is probably why they were on meds.