Do democraties have different foreign policies than authoritarian governments? The first part of the work opens the debate, with historians and theoreticians. In the second part, comparative views are proposed, with pragmatic analyses, historical cases, and the analysis of the foreign policy of states, in different parts of the world, moving from eastern and Western Europe to the United States, and from Latin America to Africa. Un ouvrage fondamental sur une question grave et pertinente: existe-t-il un lien entre le type de régime politique et les politiques étrangères mises en oeuvre?