What takes options out of play for the government is a belief by them that to use those options would do their efforts more harm than good. Why doesn't the government drop bombs on demonstrators in the streets of Washington DC? Because it would lead to a growth rather than diminution of the opposition; it would strengthen rather than weaken resistance. What determines the government's choice of tactics is their estimate of our response, and of the response of the population at large to the tactic's use.
What will protect the most militant dissenters is huge numbers of less militant dissenters who would be horribly upset at the forceful repression of the militants. What will protect huge numbers of less militant dissenters is a population at large that would be horribly upset at the repression of the dissidents.