Well, in a way, you are right. That's what happened amongst white people. They used to raise the KKK, Neo Nazi's, Skin Heads, etc. And mobs of black people didn't reduce their numbers, the legal system did in chorus with civil rights groups.
But I'm right also. In the place of the "gangta's", as you put it, needs to be more African Americans in the legal system. More judges, lawyers, district attorneys, and most of all more police officers and murder investigators. And even more African Americans in federal agencies like the ATF, FBI, etc. Not just African Americans, but all minorities.
Did you forget the /sarc tag? You must have a very naive view of State Power. Government is inherently evil. Our Founders knew that as they are good people in government, very, very evil people are attracted to the power that can be wielded by the State.
If our government as currently constituted would over night have the "minorities" you wish to be in all these agencies, then all H*ll would break loose. One has to be naive to believe the situation would improve if only more xxx would be in government.
It's sad but the majority of blacks are enslaved by the leftists evil mentality. Do you want 10,000 Holders at all levels of government?
Do you desire our Republic to turn into a Bosnia?
The entire state of tension between the races is absolute result of action by leftists inside government -- via the The Great Society (and many other such programs), leftist infiltration of the MSM, education etc.
Nothing will change until the Power of the State is drastically reduced; all the welfare programs can be phased out; and the leftist infestation in all our institutions negated.
At this point it seems there is no realistic solution. I fear things will get extremely ugly before there is any hope to turn things around. Very dark days lie ahead.