Really Long Link
Mass murderers are not new creations, folks. Serial killers aren't, either. What could be the cause of such crimes against innocents? Could it be the ever cheapening of human life? Abortion on demand right up to the due date is a good example. If we can kill other people as they try to navigate the birth canal, why does anyone even blink at killing those already born? From television to movies to music, killing isn't something real anymore. War is the sterile act of sending drones or dropping bombs on the enemy (except to our military, fighting the real kind of war, of course). Our society is bombarded with video games devoted to killing others. It's just a game but helps to desensitize people.
Ask the victims of a serial killer or a mass shooter or mass stabber if they feel better, knowing that society is unfeeling toward them. Ask someone who is bleeding if they give a rats behind about why the perpetrator attacked them. They won't be nearly as interested in the why's as they are in whether an ambulance will reach them in time.
I read somewhere that one mayor canceled a memorial service for a slain officer but attended the funeral of the man who shot him to death. How's that for getting things wrong, folks? We honor the wrong people and ignore the real victims of our societal ignorance.
These things will continue to happen until we, as a society, force them to stop. Guns, knives, etc. don't act alone to kill. People who feel entitled or aggrieved for real or imagined reasons are the killers. Their weapons matter much less than their motives. I'm pretty sure the Pennsylvania school was a "gun free zone" and the knife wielder felt safe to rampage at will.
Now, that being said, who wants to ban all items with blades? Why not have "knife free zones"? Or maybe "self defense forbidden zones" while we're at it?