You're right, it will never fully go away, and violence will always happen, but I think if we look at why people turn to gangs and violence, and address those issues the "need" for hand guns will drop. People join gangs for various reasons, be they economic, or social pressures, amongst others. So by ensuring that people are safe, well paid, a roof over their heads, full bellies, parents being around, robust before and after school programs, etc gangs wouldn't have the same pull factor

https://nationalgangcenter.ojp.gov/spt/Risk-Factors