The US consists of 50 states, a substantial majority of which have fewer people than Norway. In other words there already is a convenient delineation to use for separate systems; and there already are state-level penal systems.

For the handful of states where the population is more than twice as big or so, there are easy regional separations you could make.

These kind of problems are easy to scale because they partition trivially if there are aspects of the system that does not benefit from scale.

Now you also make the argument it makes it easier to fund these programs in a smaller more homogeneous population. If you mean that getting political agreement to funding is easier, that may be a point. But then the problem is not emulating it, but lack of will to emulate it.

I mean, ok, as a political idea that can be powerful but I don’t see it having anything at all to do with the truth. It’s just absurd …

-- "It's so big!"

-- "What can we do, the states decide for themselves!"

It often seems like the same people are able to hold either view depending on the question.

If, say, Minnesota wanted to have a prison system like Norway's, what's stopping them?

You are correct that states in the United States differ from one another in how they set up their prison systems. (Two other facts, in relation to other comments in this thread, are 1) most prisoners in the United States are in state prisons rather than federal prisons, and 2) most prisoners in the United States are in prison for offenses other than drug offenses.) I live in Minnesota. Minnesota actually does emulate Norway more than it emulates many other states of the United States. It has a lower incarceration rate than most states, and it has a higher level of public spending per inmate than most states, with single-bunk cells being the aspiration (and, for a while, the reality) to a much greater degree than in most state prison systems.

I once had occasion to tour Minnesota's maximum-security prison at Oak Park Heights[1] as an interpreter for a human-rights lawyer from another country. The lawyer, who knew the prisons in his country very well, was amazed at how clean and spacious the Minnesota prison was. He asked, in complete seriousness, "Wouldn't some people commit crimes just be put in a place like this?" A guard answered, with an equal degree of seriousness, "I wouldn't want to be an inmate here." Being in prison is denial of freedom. That's enough to count as punishment for most freedom-loving people.

[1] http://www.doc.state.mn.us/pages/index.php/facilities/adult-...

I can imagine a homogeneous population resulting in a lower crime rate although I have no data to back that up. I think a low crime rate makes it possible to have higher quality programs like this.

Assuming equivalent distribution, the higher the amount of people, the higher the amount of extremely difficult cases.

Let's skim those very difficult cases off for the moment: why can't the US make better use of concepts like restorative justice and rehabilitation for the rest of the criminal justice population?

It's cheaper; it's more effective to reduce crime; it's better for the children involved; etc etc etc.

So divide the jurisdictions to where they're manageable. We already do this - each state runs their system independently, just as each EU member state does instead of having a single European prison system.

This argument of scale comes up time and time again in these type of discussions despite being totally invalid in most cases: In most instances that are up for discussion it is not necessary to build one single large system.