Scott Alexander has a long article with a lot of graphs about to what extent the high US homicide rate relative to other First World countries could be explained by its liberal gun laws.

I have a much shorter article with what are perhaps two of the most relevant graphs.

Guns vs. Gun Murder Rates in the US states.

Blacks vs. Gun Murder Rates in the US states.

I have excluded Washington D.C., an extreme outlier with the highest percentage of Blacks (50.7%), the most gun related murders (16.5/100,000), and the lowest rate of official gun ownership (3.6%).

Feel free to draw your own conclusions.

I do think its reasonable to argue that at some very low level of gun ownership you will begin to see substantial decreases in the homicide rate relative to what it would otherwise be if only because it is true that having a gun makes killing someone quite a lot easier. But to see that you will need to see draconian restrictions of the sort you have in Japan or the United Kingdom, where it is next to impossible for a normal civilian to acquire firearms of any sort.

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