I responded to "Until one of them shoots down ONE OF his satellites and ruins LEO for everybody." And furthermore, the rest of my comment covers a scenario where many satellites are hit instead of just one.
The precedent is set once one is shot down. At that moment, SpaceX loses control over Starlink because it becomes clear its decisions carry military implications for America as a whole. (Nobody will expropriate it. But laws would need to be passed to ensure Bezos going on a bender won’t start WWIII.)