The interesting Politics SE question To what extent can a government control satellite internet compared to internet from a local ISP? asks from the perspective of politics and international law, but here I'd like to ask about technology.
The jamming of short wave radio news broadcasts has a long and colorful story, but there are several differences between that technology and blocking satellite constellation-based internet access.
Those satellites will be transmitting tens of watts only, and only over distances of hundreds of kilometers.
However signals will take advantage of a far wider bandwidth than a voiced news broadcast over AM radio and utilize substantial error correction and spread-spectrum techniques.
Also, unlike short wave reception of yester-century, the far-shorter wavelengths used by satellites mean that reception antennas can be quite directional. Compact, flat, computer-steered phased array receivers will soon become commonplace.
Question: What is the technical feasibility of a country at least partially preventing use of internet from satellite constellations? Consider blocking for large cities or population centers as one example of partial blocking.
update: @lijat points out that prevention doesn't have to be jamming, it can also take the form of detection/prosecution since conventional internet protocol use requires bidirectional communication; to get something using a satellite server (or whatever they are called), you have to request it and probably do some other handshaking.
Ideally, an answer should be based on citable studies or basic engineering principles (e.g. power-bandwidth product) rather than oratory or generalizations.