Yugoslavia’s expulsion from the Cominform has been perceived as a struggle between individual leaders and/or a conflict between “national” and “international” communism. We offer an alternative explanation of the dispute rooted in the origins of the Cold War that is based on misperceptions commonplace in the post-WWII era. The era involved the altered postWestphalian pattern in which two formerly isolationist powers, neither based in continental Europe, suddenly found themselves in global competition. Both lacked an established history of peacetime interactions in gauging the other’s behavior. Untried postwar choices entailed behaviors as new for the initiating powers as for the powers that reacted to them. Such a novel situation also characterized relations within the emerging Soviet bloc, critical for the Tito-Stalin conflict. The Western Alliance emerged gradually through negotiation and the domestic politics of individual states. East European states “friendly” to the Soviet Union implied a policy question rather than one of regime. The Cominform idea of a militant bloc of socialist states was implicit in Stalin’s postwar approach. Tito shared Stalin’s view of a socialist bloc as a basis of the European order; he considered Yugoslavia uniquely positioned in Southeastern Europe. Tito’s militancy threatened to provoke an Anglo-American response, menacing the socialist project in Eastern Europe. So strategic a difference meant Tito’s incompatibility with the Soviet project.