I see your general point, though it seems to me to make a slightly-too-strong connection between the US Gov't and its policies and interests and Starlink's (that said, if the two were fundamentally at odds it doesn't seem like Starlink would be offering to provide access to Iranians...)
Let's say it's not even the explicit, Musk just suddenly struggles to find suppliers for his factories in China and his deals to buy raw resources in China start to get delayed.
More realistically, they'd be more subtle. Perhaps Tesla would hit supply chain issues at exactly the wrong time, or they'd announce an extra $100b investment in industries directly competing with Musk's companies. Tariffs are also a thing. They could simply adjust them (up or down).
If you have a working model of how it can be done without global nuclear war, there's probably a Nobel prize waiting for you. Extra credit if you can avoid knocking out every other satellite in LEO and the space stations.