After slavery freed slaves didn't leave the place they knew as home.People switching countries is not going to happen so America is just going to keep getting worst because of republican and centrist democrat policies.I think most progressives just accept it thats why we don't complain nearly as much about crime as conservatives do.We know if this country keeps its republican and centrist democrat policies and our representatives in Congress remains whores for sale to the rich nothing is going to change.
As previously stated low aptitude racists will usually blame problems on other races but countries like England,France,Canada,Japan etc don't imprison minorities as much The US does.
There are more differences with other Western developped countries: "Children and adolescents in the United States were more than 36 times as likely to be killed by gunshots as their counterparts in other high-income countries" https://www.advisory.com/daily-briefing/2018/12/21/child-death