If you're talking about violence used to uphold their rule, you can't separate domestic and foreign violence. All those people living, working, and dying young in atrocious conditions outside of the US for US prosperity, all those people gunned down in the dark or in protests against their government's subservience to the US, and all those people murdered in wars and 'conflicts' and by sanctions to further US interests must be counted.

Otherwise you're doing that thing where you redefine violence in such a way that distorts the picture. It doesn't matter whether you now explicitly mention the US because by nature of a comparison, the US is implicated, anyway. Likewise, replace US for every other government in the above equation for the true figures of how violent a state is in its own protection.