The reality is that we don't have the tool and die, manufacturing, assembly lines we had after a year of lend-lease.
Manufacturers then of various consumer goods (Sewing machines) were converted to making weapons, manufacturers of vehicles to making trucks and tanks. We had the foundries, the shipyards, and the people who had some basic skills to train to man them (regardless of sex).
Nearly one in five (17%) lived on a farm in 1940, in 2020, it's down to one in fifty (2%).
Granted, that is not the only place to acquire blue collar skills, But the rural population had dwindled from 43% in 1940 to 17% in 2020, and of the population groups I have met, those most likely to acquire skills associated with self sufficiency were folks in rural areas. Those same skill sets transfer well into other blue collar tasks as well, and the tendency to not specialize, outside of profession, makes for a more versatile workforce.
Those women, too, were robust in the sense that just doing the wash involved a lot more physical activity, unlike after the advent of Automatic Washing machines and power wringers like this ad from 1945 shows.

"Saves 90% of your heavy lifting!"
Which means women were accustomed to doing 10 times as much physical labor before the war (and that's not counting farm chores, milking, or any of the other myriad tasks a homeowner/housewife/farm wife did, often without the benefit of power tools).
'Rosie' already had a pair of 'guns' before she took up riveting or welding on Liberty Ships.
Times have changed, and granted, so has manufacturing, with industrial robots and CNC milling, for a couple of examples, but staying out from between things that move and can hurt you and something you can't move is still important. Those who aren't used to that sort of environment are far more likely to gt hurt. And with the questionable destiny of our electrical grid (depending on wind and solar), working three shifts at the weapons plant might not be an option.
At least one shift will be in the dark.
I salute our predecessors, and note that in terms of being ready for all-out conflict, we all have a long way to go to catch up.