Résumé : This research aimed at examining the possibility that certain social representations of peace and war are, more than others, (in)compatible with support for warfare. It also aimed at investigating the weight of political culture on the realization of this possibility. Using the framework of social representations theory (Moscovici, 1961=2008), this study surveyed undergraduate students from 3 universities located in 2 countries: the United States and Denmark. Analyses conducted at the cultural and individual levels (Leung, 1989) show that the notions of peace as social transformation and of war as direct and indirect violence tend to be more prevalent among anti-war supporters and Danish participants, and indicate that the values and ideas of peace and war that are most incompatible with support of warfare are equality, fear, and poverty. Results are discussed with respect to their theoretical contribution and policy implications. Citizen peace activists developed ideas, analyses, actions, and organizations that established them as an irrepressible force. Nonetheless, they consistently failed to convert their countless efforts into the kind of political effectiveness that might move them into the main currents of American life. There were two reasons for this failure. The second was their overriding commitment to the peace of justice, freedom, and liberations within a conservative political culture that attached the highest value to notions of order, security, and stability. (DeBenedetti, 1988, p. 222). © Taylor & Francis Group, LLC.