alt Hacker NewsStill "subject to the jurisdiction of". US law doesn't currently have a law allowing them to be conscripted, and it would be very ill-advised to do so and it would cause a lot of diplomatic backlash, but it certainly could pass such a law if it chose to.
So people on a work visa are "subject to", specifically because of two criteria (income tax and conscription) which must both hold, at least hypothetically? What if the US passes a constitutional amendment explicitly saying that foreigners on work visas cannot be conscripted, would that, by removing the hypothetical, have the implicit effect of making such people no longer "subject to" its jurisdiction?
I think your take on this is overly complex and silly.