I’m surprised that you did not mention - at least in this recap - the high degree of cultural homogeneity in the Scandinavian countries as a major source of their cohesiveness and ultimately happiness. Not to mention a largely white and highly educated population that has avoided the brunt of European wars and has largely remained politically neutral. From my experience, the predominant culture was formed from their Christian roots, and kept alive by a strong tribal instinct that has led to a balance between strong capitalist and commercial trading roots, and an impulse to support those on the lower rung of society. This has all been threatened by the high number of immigrants that have arrived who come with a very different cultural background and are not broadly accepted as a member of their tribal in-group.

While there is a lot to admire about these countries, this model could not simply be translated to the US, with a highly diverse multi-cultural population.