Greenwald writes:

As frustrating as it can be, this sort of day-to-day pressure on individual journalists and political figures is the most effective weapon possessed by blogs, websites and other organizations devoted to forcing into our public discourse various perspectives and narratives which are otherwise excluded. [...]

The point here is that changing our public discourse is a slow, grinding, difficult process. Any changes that occur, any progress that is made, will be made only incrementally, one day after the next. Each individual change is usually so slight as to be imperceptible, but aggregated, those changes can be substantial. [...]

Defeatism can lead one to believe that there is no progress at all and that progress is impossible. Impatience can lead one to conclude that the progress is too slow and incremental to matter. But slow and incremental progress of this sort is the only kind that is viable, and ultimately, the only kind that really matters.

Good words, and a good reminder.