Using a gun to kill can be a heat of the moment thing. Saying that "guns don't kill people, people kill people" is trotted off by the American gun lobby all the time. If you have a gun under your pillow, or under your seat in the car you are more likely to reach for it and start pulling the trigger if someone upsets you.
The wording of the American amendment on rights to bear arms is always debated, in spirit it is to maintain and equip a trained milita for the protection of the country. Not to allow every untrained Tom, Dick or Harry to brandish one.
In the UK carrying a gun is pretty much illegal, especially a concealed handgun. There is not much problem with gun crime amongst the general population, just the criminal gangs that obtain guns on the black market.
Incidentally shooting a guy in the face as he runs towards you is self defence, shooting him in the back as he flees with your money and jewlery is murder.
Setting up shooting ranges in Qatar and only selling sports or hunting guns after a set course at the range would be a far safer way to go. There would be no heat of the moment purchases and the instructor would have some chance to asses how stable the participant is before issuing a license.
It's similar to training people in martial arts, a black belt in Karate etc is lethal, but he doesn't go round killing people, because he has been taught a deep respect for his art at the same time.
Teach people a respect for their weapon before you sell them one.