This sort of feels like the "how do we define a recession" debate. You can establish some guidelines, but I think there's also a sort of "I'll know it when I see it" qualitative type judgement too. I'd say if you can still make lots of money writing apps for scheduling dog massages and aren't persuaded to go pick up a rifle or work an ammunition press, we're still a ways off from a real world war.
Ukraine has implemented a draft, but software developer is still a highly paid position there. Many other countries have compulsory military service. So that really depends on your perspective. The US is different due to its power and geography. The draft in the US was hugely unpopular, so is likely but going to happen again, at which point, by that definition, we'll never get there. But, like you said, "I'll know it when I see it."
