Some previous decisions around the 2nd weren't very giving. The 9th Circuit just said that it's not an individual right. Anything is possible, it all depends on which way the wind is blowing in the courts when and if they decide to take it.
The question is will you go along with something that you know is not true just because the SC said so.

No, I didn't know it was possible to enter into voluntary slavery. I'm fairly sure the labor laws would have something to say about that.

I'm not saying the military is slavery though I never said such a thing. There is a difference between involuntary servitude and slavery.
Look at the qualifications of Section 1584 of Title 18. Compelled military service does fit.
You seem to forget that rights are not contingent on the situation. I have a right not to be forced or coerced to do something with my body against my will, PERIOD. There is no if, and, but or who about it.