Human beings only have two ways to deal with one another: reason and force. If you want me to do something for you, you have a choice of either convincing me via argument, or force me to do. When I carry a gun, you cannot deal with me by force. You have to use reason and try to persuade me, because I have a way to negate your threat or employment of force. So yes, I agree gun is civilization.
I would rather leave weapons in hands of police. I don't want to be shot by a policeman just because he is afraid that I might have a gun.