Strategic Interdependence in Political Movements and Countermovements

Collective action is the result of the efforts of groups consisting of many individuals. This gives rise to strategic interactions: the decision of an individual to participate in collective action may depend on the efforts of both like-minded and opposing activists. This paper causally studies such strategic interactions in the context of left- and right-wing protests in Germany. In an experiment, we investigated whether randomly varied information on turnout of both like-minded and opposing movements impacts activists’ willingness to protest. In response to information about high turnout of their own group, left-wing activists increased their willingness to protest, consistent with theories of conditional cooperation. In contrast, right-wing activists decreased their willingness to protest, consistent with instrumental accounts and free-riding motives. For both groups, there was no significant reaction to information about turnout of the opposing movement. The results highlight substantial heterogeneity in strategic interactions and motives across the political spectrum