The problem with firearms isn't their destructive capacity, it's their 'user friendly' interface. Anyone can fire a gun, and any competent person can make one, so you cannot ban firearms without erasing the memory of guns ever existing. The only reason the entire human race is not dead yet is because of the exclusiveness and difficulty to create atom bombs. It is a condition of our race to be violent and brutal, because we will always abide by the Law of the Jungle. Banning guns would have not saved that dog, but reducing the creation of them can help. Unfortunately, a lot of people would be out of work, and a lot more people will be angry that you are limiting their "defense"
It is my personal belief that we should restrict the sale of handguns to the public, because honestly there is very little use for them in a defensive situation. If a criminal breaks into your home with a gun, and you have very little time to think or react, a shotgun is almost guaranteed to injure the criminal if you so much as point it at them. A glock .44 is not a guarantee, and is used plenty more for the assistance of criminal activity than a shotgun, merely because you can conceal the weapon more effectively.
So why are handguns open to the public? Perhaps some of you can enlighten me, because I just don't know.