ABSTRACT
Actual participants in contentious politics—street-level activists, citizens who band together against polluters of their neighborhoods, national leaders bidding for membership in the European Union, and many more—feel threats and opportunities vividly. They organize to fend off threats and keep themselves alert to new opportunities. While threat and opportunity form visible features of contenders’ political and economic environments, attempts to specify how they work have frequently stumbled. Two problems have proven extremely difficult:
first, distinguishing between systematic variation in the surroundings of political actors, on one side, and variations in the responses of the same actors to those surroundings, on the other;
second, connecting the two: discerning how surroundings and responses interact.
