Tee, with all due seriousness, it seems that you have concluded that anytime "any" person possesses a firearm, it mutates their way of thinking, turning them into some aggressive maniac, if not worse. The point that Plane, Ami, Professor, and so many others have made, is that those who have gone thru significant firearms training & safety, are in large part MUCH safer in their handling of firearms than the punk kid on the street, who might not think twice in killing you or your loved one. I can't count how many stories of lives that were saved by the presence of a firearm, as well as the many other tragic scenarios where a person with a firearm would have prevented some mass carnage/killing by some crackpot.
You're applying some mutation of a person's thought if someone is simply possessing & handling a gun.....which likely IS the case for those hoodlums, punks, and gang members. They probably are much more likely to pull it and use it, if they have one. The ones who are much more likely to stop said punk killers, if the police aren't around, are precisely those who have been trained to handle a firearm, and are carrying a concealed weapon.