Again, this is not what's being discussed. What you discuss is a worthy question in its own right but it in turn has nothing to do with what Gingrich said. And incidentally, the Nazis are a terrible example to use for that strawman, you should use either the Roman Empire or the Soviet Union. They at least did slavery right, the Nazi economy was a house of cards that awaited a whispy breeze and it would collapse into dust and ruin. So not only something completely different from the OP, a poor further example of that complete difference.

You can make a case that Gingrich's idea is more nuanced than it's made out to be here, but you're arguing something completely different and unrelated to what Gingrich said.