Of the myriad terrorist organizations that emerged in the late 1960s and the 1970s, those supporting the destruction of socialist Yugoslavia and the establishment of an independent Croatia were among the most active. This article explores the geopolitical context behind the radicalization of certain segments of the émigré Croatian population in the three decades following World War II and the processes that led them to adopt terrorism as an acceptable form of political expression. Specifically, it examines how changes in the realities of the Cold War political landscape during the 1960s and 1970s directly shaped the strategies of Croatian separatist groups outside Yugoslavia. These developments led Croatian radicals to cultivate a culture of abandonment, betrayal, and persecution, in which the Croats were portrayed as a nation of victims without allies. This helped precipitate a radicalization of the separatist movement, as many within the Croatian diaspora were increasingly convinced that only “self-initiated action”—that is, political violence and terrorism—could hasten the establishment of an independent Croatian state. Difficulties in dealing with the realities of Cold War international politics also led to the emergence of significant cleavages and conflicts within the émigré separatist movement, which further helped frame the processes of strategic thinking among radical activists. Drawing evidence from state archives and the political writings of radical émigré Croatian separatist organizations, the article traces the trajectory of radical Croatian separatists from staunch supporters of the West to desperate and disillusioned advocates of realpolitik thinking.