Before we get deep on the subject of 'guns,' violence, and causation factors, I would again point to this old movie I watched.  This guy goes to a specialty shop where powerful weapons are made and under the provision that money is no object he asks for a very powerful weapon to be made for him.  When the buyer goes in to pick up his new weapon he ask's the builders if it is safe but powerful?  The builder says, "This weapon is a mighty force, with one exception, , , one slight, , , imperfection."
"What, imperfection?" the buyer ask's.
The Chief builder responds, "The imperfection 'EVERY' weapon has, , , it's, 'User.'