Certainly gangs could be played against each other more effectively ( I had one LEA official semi-jokingly say we should work to convince them that one needs to kill another gang member to become a gang member. Goal was zero growth and a reduction of such initiation homicides against innocent civilians).

But to reduce the growth and influence of gangs one has to address the psychological reasons why people join such organizations and either mitigate those causal factors or offer better alternatives, or both. Reducing the number of illegal revenue venues would also help (drugs, prostitution, guns, human trafficking, etc). I suspect a more effective integration program for legal and illegal immigrants; coupled with a concerted effort to vastly reduce the size of the prison community in the U.S.

Bottom line is that much of the recent growth of gang numbers and influence is a result of domestic policies that have nothing to do with gangs directly. In that way, gangs are very much like insurgent organizations indeed. A response to ill-formed or implemented domestic policies.