But North Korea was once a VERY PROSPEROUS nation
One thing we learned in my Comparative Econ course many decades ago was that Socialism DOES rapidly industrialize an economy, at least initially. However the top down command and control economy is highly inefficient; thus the benefits do not last long. The products that are produced are produced only to meet the quotas, thus there is no quality control.
As far as the “workers” starving; it happens in all socialist nations. This is because the incentives are all wrong.
However; the left feels that their ideas can never be wrong - so when they don’t work it is because we just didn’t do them enough. This is why even though socialism has failed miserably every place it has been tried they insist on trying it again. It just CAN’T be that it is a bad idea!
It doesn't.
[I was taught the same thing in the 1970's.] If it were true, there would be no reason why the initial successes could not be compounded: Aggregate Demand creates more demand. True growth creates more growth. This is why socialists believe in "stimulus." It's false.
What command economies -- including Socialism -- actually do is very rapidly consume all assets. Comparatively free market economies, even feudalism and mercantilism, create wealth not all of which is consumed. When Socialist revolutions come along, they spend it all. When it's exhausted, since all of the "growth" was created by borrowed money, there is nothing left to sustain it.