edit- follow up question
“a well regulated militia”. since the amendment was passed, and since the US has a military, has there even been a militia? would you trust your random neighbours loading up and marching against something? or would you expect law enforcement to crush it?
seems like the amendment has become “the locals can have guns and murder each other”. Nothing to with a “militia”; or defending your country.
I imagine defining what counts as “self defense” is difficult. A lot of the gun violence is justified as “self defence” (whether that is accurate is a different story), whether it’s trying protecting family/friends, your property, or yourself. It’s a lot easier to come up with a statistic of how many people got shot by a gun.
And you are correct that more guns is correlated with more gun-related violence, there are plenty of studies on this for many different parts of the world. When I was in middle school, we learned about this in geography class, with data points in Australia, the US, China, and various countries in Europe, and there was a very strong relationship between number of guns and the cases of gun violence!