Even space telescopes have been built on the skeletons made for spying, and rockets in almost any form were weapons before they were carrying peaceful missions. That we have Russian, American, and European components communicating together at the ISS is kind of a lovely, if temporary, closure of the circle.
From a certain point of view ICBMs are a method of communicating.
Trajectorial calligraphy is a subject in some schools where individuals who like to communicate unconventionally study.
I'd wager starlink is mostly military with the cover of civilian use case.
search "Declassify Elon Musk's space-based weapons program before Biden leaves the White House"
There's the program called Starshield, that's part of the miltech side of the program. One of the military uses is using the starlink constellation signals as a passive SAR for the whole planet with millimeter scale accuracy.