We can carry our pistols and long guns in public without a permit around here (Fairfax County, Virginia), and this area is about as urban as Queens, Brooklyn, Staten Island, Newark, etc.
Our murder and violence rates are far lower than those of any New York borough.
It has something to do with controlling behavior and devoting police resources to that task.
The people in your area have had the sense not to become suckers and trade liberty for security while abdicating personal responsibility.
Selling drugs in order to curb drug use, selling or buying black market guns in order to curb black market gun sales is logically twisted first, counter productive, tempting and dangerous.
Brooklyn NY and Fairfax Va are like apples and oranges. I was in Fairfax 2 months ago to visit the NRA. Most of Fairfax is a pretty nice place to live-- most of Brooklyn is like a 3rd world country. Again, apples and oranges- can't compair the two.