I remember a common saying that's bandied about Hacker News: a 10x quantitative difference is a qualitative difference.

Well, America's violent crime rate is 10 times higher than Europe's violent crime rate, so make of that what you will.

Parse attempt: there are too significant systemic, social differences to meaningfully compare process&results between countries.

Half the point is that systemic differences contribute to different outcomes, so lets change the system. What a sad rejoinder to argue that the system is a force of nature.

Some bits of the system we can change with effort. Urban poverty, etc, can improve. We can have a better criminal justice system.

Some are cultural bits in subpopulations that are resistant to change; we can work on it, but it's not clear how much of an effect any intervention will have.

There's some other structural ones that will be extremely difficult to change-- we have the some of the most dangerous places in the world next-door in Latin America.