And, all of America is basically one big country-level study of the effects of constant gun violence on communities.

You're getting the cause and effect the wrong way around. The gun violence is caused by society being a hyper-exploitative atomised hyper capitalist hellscape with no community and only pain, suffering and struggle. It's not the guns causing that, people turn to the murder suicide option because this society design fries their brain. People could do this anywhere in the world, but america is unique in having an absolutely massive problem with it, while it is also unique in being the only developed country without consumer protections, without basic amenities, without healthcare, without welfare safety nets, without care for the homeless, etc etc. It is a land without love or comradeship.

You want to solve this? Start with redesigning society. Start with redesigning the urban environment that atomises people and prevents community. Start with healthcare and safety nets. Start with making society a place for people instead of a place for the rich to exploit.