It's unpopular to say, but mass incarceration works at mitigating crime. Tough recidivism laws gets criminals off the streets. It also acts as a deterrent. One can point to high relapse rates or that there is still a lot of crime, but one must consider the counterfactual and control for demographics. Controlling for demographics and culture, would there be less crime with more lenient sentencing? I think not. It's possible that societies where leniency works are advantaged culturally or demographically in ways that the US isn't, so it works better there. Or maybe citizens or politicians have higher tolerance for crime.