This chapter explores the mutually reinforcing transformations in American state-society and foreign relations engendered by the First World War and its aftermath. Scholars have long recognized the war as a critical event in the emergence of American global power and the concomitant rise of Wilsonian liberal-internationalism. Yet it is the post-World War II period that is typically designated as the decisive moment of epochal rupturing in US history. This chapter seeks to problematize these notions of a sharp epochal break, demonstrating the more fluid lines of continuity between the two periods contextualized within the longue durée of American state-formation. In particular, it highlights the ideo-political and cultural antecedents to Wilson’s liberal internationalist order-building project and its relationship to the defence of white supremacy at home and abroad. In so doing, the chapter demonstrates how the post-1945 US-led Western liberal international order was built upon white supremacist foundations and a particular form of racialized anti-communism that had emerged decades earlier. US hegemonic practices were, on this view, constituted in and through the racial articulation of an anti-communist “common sense” defined by a militantly normative Americanism that found its roots in the First World War period.