The U.S. embarked on a program of global supremacy eighty years ago, and American political leaders and policymakers chose this path much earlier than is commonly believed. To that end, they invented a myth of an “isolationist” America during the 1920s and 1930s, and that myth has been used ever since as the justification for dominance. In the earliest days of WWII before the attack on Pearl Harbor, U.S. policy planners were already imagining a world order with the U.S. at its apex, and they made sure to redefine internationalism so that it applied only to supporters of this new strategy.

These are some of the valuable findings that Stephen Wertheim has brought together in his excellent study, Tomorrow, the World: The Birth of U.S. Global Supremacy. Wertheim shows that proponents of this new role of supremacy did not fear an attack on the United States, but sought to avoid being limited to a hemispheric role for fear of being “isolated” in our own part of the world. He documents how the thinking of policy planners in the late 1930s and early 1940s changed in response to developments in WWII, especially in Europe. The planners envisioned a postwar world policed by the U.S. and Britain, and in order to legitimate this much more ambitious global role in the eyes of American public opinion they dressed it up with the creation of a new international organization in the form of the United Nations. Along the way, the supporters of this new dominant role made sure to cast their internationalist critics and opponents in the worst light by conjuring up the specter of “isolationism.” This was a word that had hardly been used prior to the mid-1930s to describe a view that no one actually held, but it was then applied liberally against anyone that questioned the drive for supremacy.

Wertheim’s account of this period is compelling and insightful. It is a short volume, but it is very rich in detail. Policy planners were already discussing a U.S. role in terms of supremacy and domination in late 1940. Even before the U.S. was formally at war with the Axis, U.S. planners were drawing up proposals for what one analyst simply described as “world domination by the United States and the British Empire acting in close and continuous collaboration.” The blueprint for America’s postwar role was already being drafted before the U.S. entered the war. The objective, as Wertheim says, was “to maintain armed primacy,” and this was already the goal in 1941 before Japan attacked. This is very different from the standard interpretations of the period, as he makes clear: “Rather than react defensively and belatedly to an objective threat, as most narratives of this period presuppose, U.S. elites did almost the opposite. They expanded their definition of national security, deeming the United States to possess an overriding interest in avoiding ‘isolation’ within the Western Hemisphere.”

Global supremacy was not the logical or inevitable culmination of American history. It was the result of a series of contingent decisions that U.S. policymakers made during the 1940s that laid the foundations for U.S. foreign policy thereafter, and it required the complete reimagining of America’s place in the world. Wertheim writes:

It was this work that wartime interventionists carried out in the name of internationalism and the U.N. Promulgating a narrative in which American foreign policy swung between the poles of internationalism and isolationism, they demolished the intellectual resources that had countered armed supremacy. Their narrative expelled noninterventionists from the ranks of internationalism and the sphere of legitimate discourse. The restraint of American power became the height of introversion and selfishness. By extension, no vision for a better world could fail to include the United States as the supreme power and defining agent. Once opposed to nationalism and defined by the transcendence of power politics, internationalism came to denote U.S. world leadership above all. Thus interventionists did not merely argue that an internationalism without U.S. supremacy would be undesirable; they rendered the prospect conceptually impossible, articulable only outside the terms of American political discourse.