I find curious the Starship business ROI discussed here mentions almost exclusively Starlink and the moon.
Putting weapons in orbit seems a very likely goal, given the attitude of the current US leadership.
They felt confident enough to recently acknowledge publicly their existence:
China launched some classified mission just last week which was quite possibly weapons for disabling other satellites.
Not just US - plenty of other countries will want to do the same, and there are only going to be a couple of countries with cheap payload capability.