Let me guess, you live in Chicago.
"We already have that." No, you don't already have that. You live in an urban fascist hell where guns are de facto banned, but every gang banger has one and there is much violent crime.
I on the other hand, do have that. I live in a state that recognizes my God given right to arms. I live in an area where there are lots and lots and LOTS of guns. Almost everyone I know owns at least one gun. Many of us carry them. Shootings in my area are rare.
So explain to me why it is that in places, like where I live, which have very high rates of gun ownership among the general populace, crime is low, yet in places like where you live where it's nearly impossible for the common honest citizen to legally get a gun, crime is high?