I'm sure it justifies a much more nuanced consideration, but at a crude economic level, I suspect gangs provide protection and economic opportunity in exchange for physical and legal risks; Norway provides both of those opportunities, to a high degree and to a broad section of society (social mobility in Norway is high), with much lower physical and legal risks attached, so there is competition for what gangs provide.
Also a very homogeneous population. Crime is higher among recent immigrants/refugees and their children[0]. It's hard to tease out how much is due to the prison/legal/welfare system and how much is due to the composition of society. Plus, it's a tough thing to debate openly because of accusations of racism, xenophobia, etc. In any case, it's certainly true that the US prison system is not very effective at reforming criminals and I'm sure the conditions are often appalling.
Saying "foreigners are more often criminals", while not necessarily xenophobic in nature (as in, you don't have to have strictly xenophobic thoughts to come to such a conclusion), doesn't lead to a nice and balanced conversation. That is leaving aside the correlation/causation dilemma which you're just sidestepping here (it's correlative, not causative - unless you have some sort of proof for that, which I doubt).
No that's not what I'm saying. I understand the issue is complex. I am saying that crime looks different in Norway because their population is very different than the US, and that in the parts of the population that are more similar to the US you have higher crime rates.
I never claimed immigrants are somehow intrinsically more disposed to crime. In fact, the report doesn't make that claim either. It shows that crime rates vary greatly based on where immigrants/refugees come from.
> But why aren't gangs forming in Norway? Lack of poverty? Lack of substantial immigration?
In other words, why isn't MS13 infiltrating Norway.
It's not simple, there are many causes of such a effect. But offering free education and other opportunities that are substantially better than crimes is a good guess.
You should really stay away from this kind of outgroup = scum thinking. Tribalism and makes the world an actively worse place for having you in it (as the people in your ingroup gain little and everyone loses their humanity).
In other words, why isn't MS13 infiltrating Norway, if there's no competition for their illegal activities?
In the United States, for instance, there's a huge market for gang formation, and gangs thrive despite constant fighting for territory.