Quantum-based communications systems cannot be jammed. I'm not a quantum physicist, but I have read a couple of open-source papers that suggest the People's Republic of China is fielding a quantum-based satellite communications system that we will not be able to intercept or jam. Fielding a quantum-based SatComms system in high orbit would remove it from most space junk and from existing Anti-Satellite (ASAT) systems.
Quantum-based satellite communications employs cutting-edge physics. We do not yet know how to jam or intercept these systems. In high earth orbit these satellites would be out of range of most operational ASAT systems.Add Improvement
Placing such a system in high orbit would complicate the problem of attacking it kinetically. The only way to disable such a system would be to destroy its ground station or attack and disable the satellite in orbit.Add Improvement