The Problem Is Guns
By 
Why is there so much firearm violence in the United States? It’s not complicated:
First, America has uniquely weak gun laws. Other developed nations at the very least require one or more background checks and almost always something more rigorous beyond that to get a gun, from specific training courses to rules for locking up firearms to more arduous licensing requirements to specific justifications, besides self-defense, for owning a gun.
In the US, even a background check isn’t a total requirement; the current federal law is riddled with loopholes and snared by poor enforcement, so there are many ways around even a basic background check. And if a state enacts stricter measures than federal laws, someone can simply cross state lines to buy guns in a jurisdiction with looser rules. There are simply very few barriers, if any, to getting a gun in the US.
Second, the US has a ton of guns. It has far more than not just other developed nations, but any other country period. Estimated for 2017, the number of civilian-owned firearms in the US was 120.5 guns per 100 residents, meaning there were more firearms than people. The world’s second-ranked country was Yemen, a quasi-failed state torn by civil war, where there were 52.8 guns per 100 residents, according to an analysis from the Small Arms Survey.
And there you go.