The Great Depression was almost immediately followed by WW-2. Agreed that war industry kept the economy moving but what kept the economy moving after the war ended given that the male population had been decimated (fewer consumers) and demobilization (fewer jobs)?

May I ask if you have a particular country or group of countries in mind? The issues are different for the West versus the Communist countries.

I'll add that the US was relatively unusual in having such a long Great Depression, at least amongst those countries for which we have suitable economic data, generally the countries that left the gold standard early in the 1930s (or in the case of Spain, were never on it), recovered sooner, before WWII (though typically without hitting the strong growth of the post WWII era).

Source

Bernanke, Ben S. The Macroeconomics of the Great Depression: A Comparative Approach. Journal of Money, Credit, and Banking 27 (1995): 1-28. https://fraser.stlouisfed.org/title/1169/item/2399