One note on this: the primary way that the U.S. system differs from the rest of the world is in the average length of sentence. At any given moment we have more people in prison because the people we put in prison stay there longer, not simply because we put more people in prison.

A startling fact: if you released every person in prison on a drug charge the U.S. it would still have the highest incarceration rate in the world. This is both because the reality is that the U.S. has a lot of violence and because we tend to issue very long sentences for violent criminals. This is a good thread that covers some of this: https://twitter.com/JohnFPfaff/status/1376971131039666177

The article I pulled that link from is also very good, but it might be only for subscribers (I'm not sure). This is that article: https://www.slowboring.com/p/mass-incarceration

It covers a whole bunch of stuff that's relevant to this thread -- what kind of people are in prison, what kinds of crimes did they commit, what works to deter crime, why do we have such a high incarceration rate, what effect does policing have on crime, are longer sentences a deterrent, and so on -- and I'm tempted to quote it at length, but I think the best thing I can do is just link it and leave it at that.