Musk just opened himself up to an act of retorsion. Ukraine can go as hard as they want to after him, because the rule of proportionate response doesn't apply to acts of retorsion.
You yourself conflate foreign powers and foreign governments in this very comment. Musk is obviously not a government, but he's definitely foreign and it's hard to find a definition of the word "power" that "able to shut down comms for military in a way that completely scuttles a mission that's in progress" doesn't fit.
Yeah, well, when did we start using that term? Was it before billionaires? Because if you act like billionaires are normal individuals and ignore the fact that they can function as if they can force governance on others, then you're just begging for the corpo-state instead of an elected government.
Does Musk count as a foreign power? I mean I could technically see that being the case, but your reasoning here is slightly flawed. That would be like calling Boeing a foreign power outside the U.S.