Weird. It’s almost like you didn’t listen to any of those sources I cited.
They’re 30 minutes each, so I’ll give you the short version: The Nordic nations were, prior to about the 60’s and 70’s, highly capitalist with a relatively small welfare state. They began implementing welfare, and eventually their economies started to slow. Since then, several have pulled back from the welfare state to some degree.
They also generally have high economic freedom indexes, which allows them to remain relatively prosperous despite living under 40–60% income taxes.
So, essentially, what you have are a societies that attempted to implement some of socialism’s ideas (the welfare state) and generally found that they couldn’t go #FullSocialist or even #HalfSocialist without serious fiscal consequences. Furthermore, it is the lack of socialist policies in governing the economy that has allowed them to survive this long at such a high standard of living.
