I have to say I don't like the "men caused the war, so men have to fight in the war" thing. Because while it's true that men are responsible for wars in general, I don't think it's a fair argument to make other men how are not responsible for the war, the same way that we as women are not responsible for the war to fight and get fucked in the process.

Some more valid arguments to why women should not be obligated to fight in an somewhat imminent (possible - hopefully not gonna happen) WW3 that we should use instead of the "some men are responsible, so all men have to fight" argument:

• if WW3 started tomorrow, they would first call the people who already have the training. In the US, as far as I know, there are no mandatory army service, and men and women can enlist if they choose to do so. If more men chose to enlist than women, that's on them, right? That's on everyone that enlisted, men or women. It's not the fault of other women who didn't enlist.

• in many other countries, only men have to go through mandatory army service. Women don't (that's the case in my country). So only men would be more prepared for a war. That's not women's fault. This is a governmental decision.

• now why are men sent to war before women when the situation gets more extreme and the government is done sending qualified people? There are other rational reasons for it:

1) men are physically stronger. Period. There is no fighting biology. In a war it makes more sense to get stronger people to work for you. (and sure, there are a few women who are stronger than men, but on average men are stronger and the government is not hand-picking people: the choice is made based on the average person - that's also why they normally send men up to 40yo - because they are in their physical prime up to this point)

2) thanks to the patriarchy! In many places in the world (again, my country included) it is still the woman's responsibility to take care of the children. Many fathers don't know how to change diapers (seriously) and do other basic shit their kids require. So imagine if they were to say "hey, we are selecting one person in your household randomly because equality, am I right? , so now we chose your wife and you are fully responsible for your children". Those men would not be able to care for their children properly.

Anyways, these are some arguments that are more valid then the "some men are responsible for war so all men, even those not responsible and against wars, will be obligated to fight" argument.