There is no “solution”.
You can’t stop every drunk diver.
You can’t stop every terrorist.
You can’t stop every texting person behind the wheel.
You can’t stop every madman with a gun.
As long as people are free, they will be free to do as they will and pay consiquences for their actions AFTER the act. Every asshole, lunatic and paranoid freak is free to do what they want.
Anybody want to reference the recent Chinese school mass stabbing? Yeah nobody died but it didn’t stop him from stabbing 30 kids.