It wiped out a generation of men in France. There was a great novel “Once An Eagle” about a soldier who got in after the Spanish-American war and served into Vietnam.
Great writing, and in one passage he talks about France after the war when there were no adult French men around, and women from childbearing age through elderly grandmother stage were all dressed in black.
Inter-War France was a train wreck, it’s no wonder it was such easy pickings for Hitler.