Being paid some amount of money doesn't magically make it not slavery. Obvious counterpoint: what if a plantation owner "paid" each slave a single modern-day penny a year, would that make it okay?
> and could be expected to be discharged at the cessation of hostilities
Being let go when you're no longer needed doesn't stop it being slavery either. Would you no longer be a slave if the plantation owner released you after the harvest season? You'd just be re-captured for the next harvest, of course - either by the same owner or a different one.
> Conscription is as old as society itself.
So is slavery. That doesn't make it okay.
Definitions of forced labour, like the ILO Forced Labour Convention of 1930 for example, have to explicitly include "by the way, it's totally okay if it is done as part of mandatory military service" clauses for a reason.
There are obviously differences between traditional slavery and conscription, but conscription is still way closer to forced labour than it is to consensual service. Just look at what happens when you try to leave, for one!
I think it's important to acknowledge that conscription is a violation of human rights, and absolutely a violation of human autonomy and dignity.
The reason it exists is because historically, the primary source of military power has been the number of armed humans you can put on the battlefield. That's much less true now, but even in WWII the technology wasn't yet up to that point.
And while the US did not end up being materially at risk in WWII (aside from some very small exceptions like Pearl Harbor), that was not a guarantee going in. The Nazis were hellbent on wiping out all opposition to them, and the fear that, if Europe was lost, they would cross the ocean to attack us was not at all crazy. Furthermore, our allies absolutely were under existential threat—and in such a situation, it's frankly irresponsible of a nation not to use conscription if that's actually likely to make a difference.
Either saying "conscription is slavery, therefore it is never justifiable" or "conscription is nothing like slavery, soldiers get treated well" ignores enough of the truth that they're misleading at best. Sometimes you really do have to deal with nuance.
Germany introduced law, your are required to notify ministry and get permission, of you leave country for couple of weeks.
Ukraine closed border for men in like 10 seconds.
Desertion has, historically, been a capital crime. Trying to paint conscription as not being a kind of captivity because "you're not legally obligated to stay in your country" is at best wildly disingenuous, and at worst just flat-out wrong.
I think you might need to take quite a bit more time to consider this issue, lest you prove your username much truer than you probably want.
And it remained so for the US in WW2, although the sentence was carried out just once.
https://en.wikipedia.org/wiki/Eddie_Slovik
Major General Norman "Dutch" Cota, who was at the execution, called it "the toughest 15 minutes of his life". For context, Cota was also present at the bloodbath on Omaha Beach, where he famously rallied troops.
Sorry for the edits confusing things. I can see earlier how you thought I meant desertion as opposed to emigration.
Dismissing the loss of freedom inherent in conscription by saying you can avoid it by abandoning your entire life, leaving your country, your job, probably your family behind...even if you do have both the money and a legal path to immigrate somewhere else, which, again, most people do not, that's hardly a reasonable alternative.