99% of males in the U.K. avoided dying in ww2 - 380k military casualties vs a population of 47 million (and presumably 23.5 million male)

I’m assuming non military casualties were evenly spread between male and female.

That was also true of much of the feudal or monarchist European wars in the centuries before WWI. In the near term before the "democratic" era around WWI wars war largely seen as wars of the aristocracy and armed forces. Merchants could usually ~freely come and go between countries at war and you could generally pass to a country you were at war with without common people seeing you as an enemy. Wars also tended to be less "all or nothing" where the other side was evil and had to be destroyed and were seen more as property and rights disputes of the elite where armed force was a negotiating tactic or strategic use to assert some particular right.

It wasn't until the scam of 'democracy' fooled people into thinking war was against the actual people of the other country that they not only scammed everyone into having such buy-in and stakes for the war but also to view the other countrymen themselves as the enemy. People started viewing the nation of themselves because their laughable miniscule influence of their vote somehow means the government is of them. (Note this was a resurface of course, there were times in history where war was seen as against a peoples rather than of the elite).

> unless they were Jewish

Cold comfort. Just decide to not be of Jewish descent then. Who would have known it's so easy to escape the attention of the Gestapo! /s