Well when you’re lagging technologically (thanks to being a new industrial nation AND having killed off most of your talented people), and “bodies” are literally all you’ve got....
There’s a great movie out called, I think, Mr. Jones.
It’s about an English reporter.
He goes to the Soviet Union in the 1930s because the Soviet Union is building like crazy while the rest of the world is dormant from The Depression.
He finds that Stalin is starving the Ukrainians so that he can sell their grain for cash and then use the money to build.
The Holodomor (sp?).
The Soviet Union was turning out massive amounts of armaments.