Democrats at least have a large faction who are willing to complain about things like drone strikes and mass surveillance even when it is their guy doing it. Unfortunately that faction isn't yet large enough to get Democratic politicians to stop doing that kind of thing, but there is some hope that if that faction consistently shows up in primaries for a while they might eventually be able to get some change.
Republicans who are willing to keep complaining even when there is a Republican president are practically non-existent so there is little hope of change ever coming from Republicans.
I seem to remember a solo republican filibustering about drone strikes, continuing to do so about FISA and also fighting the appointment of a CIA Director that not only found torture acceptable but ran a black site. Ron Wyden's the only Democrat that's been there every step of the way.
Republicans who are willing to keep complaining even when there is a Republican president are practically non-existent so there is little hope of change ever coming from Republicans.