What is the role of civic norms for social change after traumatic events, and how do those norms shape collective resistance? The present study seeks to address this urgent query by examining Sicilians' culture war against the mafia. Based on rigorous ethnographic research over a period of 7 years (2016–2023), an extensive database was created, which included 77 commemorative events, a guided city tour, 54 interviews with antimafia activists, and 89 audio–visual recordings totaling 1768 min. I introduce two analytical concepts, “informative rituals” and “transmissive rituals,” that offer a new perspective on how activists leverage the civic norms of social bonds to realize their objectives. I argue that shifting civic norms in a post‐traumatic society is not only driven by collective resistance but also requires significant time in the presence of an oppressive force. This study proposes that, for a socially traumatized community attempting to shift civic norms, prolonged and strenuous endeavors are required in order to thoroughly permeate those norms among the general public. The findings demonstrate that the consolidation of civic norms within post‐traumatic societies is highly contingent upon its temporal context and sustainability, which explains why culture wars frequently necessitate a long‐term communal investment.