Why do some communities overtly declare their opposition to violent groups, while others disguise it by engaging in seemingly unrelated activities? Why do some communities manifest their dissent using nonviolent methods instead of organizing violence of their own? I argue that ideational factors are crucial to answering these questions: normative commitments can restrict civilian contention to nonviolent forms of action, while exposure to oppositional ideologies can push civilians toward more confrontational forms of noncooperation with armed groups. Furthermore, I contend that the role of political entrepreneurs activating and mobilizing this ideational content is crucial for it to shape contention. I support this argument with a wealth of microlevel evidence collected in various warzones in Colombia, analyzed within a purposively designed comparative structure. My findings support the growing conflict scholarship that stresses that ideology matters in war, but extends its application beyond armed actors’ behavior to that of civilian communities.
