The majority of people in prisons in the US are incarcerated for violent crime. 64% of violent criminals are rearrested compared to 40% of nonviolent criminals. It really looks like the US is being somewhat efficient here and just has a lot of crime.

> Millions in prison, massively disproportionate to the rest of the world.

I recall a comparison that was done between incarceration in the US versus the UK, and the defining difference was length of sentences. The rates were otherwise similar, but the US justice system gives out sentences something like twice as long on average.

It's a large country with subtle differencies across the states but this story came to mind immediately https://news.ycombinator.com/item?id=48249747