This paper examines the domestic enablers and constraints to oversized coalition burdensharing. Using the Canadian case study, it explores the conditions under which state leaders are successful in imposing their policy preferences to a critical public, despite little tangible benefits in return. The paper develops a neoclassical realist framework which focuses on domestic determinants of alliance burdensharing, namely elite consensus, strategic culture, strategic narratives, executive autonomy, and social cohesion. This framework helps make sense of Canada's distinct case of public contestation and policy resistance by making two broad arguments. First, ineffective strategic narratives and strategic subcultures explain Canadian public opposition to Canada's combat mission. Second, an unmobilized public opinion, due to elite consensus, best accounts for Ottawa's policy unresponsiveness and hence its decision to maintain the coalition's fourth largest combat presence in Afghanistan from 2006 to 2011.