Unlike social movements in the past, she argues, today’s fast-forming, fast-dissolving movements are liable to “tactical freeze,” in which they fail to develop the internal deliberative capacity to shift tactics in response to changing circumstances. She illustrates this possibility with examples from the Turkish protests in Gezi Park and the Occupy movement, both of which had a distinctly anarchist ethos. But other social movements don’t fit this pattern. Digital activist organizations such as MoveOn.org and ColorOfChange.org have demonstrated substantial tactical versatility over the years, relying on a culture of testing and analytics that has helped them adapt to a fast-changing media and political landscape. Similarly, in the 2014 People’s Climate March, which attracted 300,000-plus protesters to New York City just before the U.N. Climate Summit, the convening groups were able to change tactics and shift their focus to increase their impact.