The concept is that if everyone has a gun, no one is going to take the first shot.
Now what kind of world are we living in if everywhere we go, everyone has a gun on themselves? Which one of you are the criminal minded and standing next to you and has a piece?
An ideal world that we are living in should be that the good guys carry guns and the bad guys do not.
It just makes it safer for the common folks to go run and hide behind the good guys who has a gun. Think in terms of a prison system.
How about we ditch all guns and we fight hand to hand combat? The bad guys still win. When they on meth, they get super strong or if not guns, they'll find another weapon to do the deed.