From the outside, it looks like the US's society and culture fosters an unusually large criminal class compared to other western countries? If people had access to education, healthcare, jobs that aren't shipped overseas, minimum wage that wasn't laughable, etc, there wouldn't be so much problems? Arguing over severity of punishment while ignoring systemic issues is silly.
Non-developed countries do not have functional law enforcement and they are highly corrupt, so any statistics outside of developed countries should be ignored.
For developed countries, none but America have such high levels of immigration nor the racial diversity America has. It is much easier to convince society to promote high-trust empathetic solutions when society is racially homogenous and shares cultural background. It’s impossible to compare America to any European country, although soon it may be possible if immigration continues
How are you measuring that? There are plenty of developed countries with a higher immigrant share like Switzerland and Australia. If you're taking about visible minorities then Canada has a higher proportion of the population.
I don't think you can make a facile pronouncement that European countries and ethnically and culturally homogenous any longer. We can't have a High-trust society in the USA when politicians scapegoat immigrants, in spite of their being more law-abiding on the whole. We can't avoid having a demoralized populace when corporate funded politicians of both parties drag their feet instead of giving citizens of the most productive and wealthy country in the history of the world parity with less wealthy countries, in terms of healthcare, education, housing, retirement and lack of life precariousness, like going into bankruptcy over medical debt...
a) much more time and effort should be focused on catching and stopping the most persistent repeat offenders (sometimes by locking them up); and
b) orders of magnitude too many Americans are currently in prison.