Few topics in modern history have received as much scholarly attention as the origins of the Cold War—traditionally portrayed as a state of political and military tensions between the United States and the Soviet Union that developed in the wake of the Second World War—and the role the Korean War played in catalyzing the East-West strategic rivalry. Hajimu Masuda's book Cold War Crucible, based on his 2012 Cornell University dissertation, makes for a welcomed addition to an already crowded field, pushing the historiography of Cold War origins in exciting new directions by building on what has traditionally been the study of elite policymakers and their decision-making processes and combining it with the study of social acceptance and participation in the construction of the Cold War.

Masuda's work is not about the Korean War. The tragic three-year fratricidal conflict on the Korean peninsula serves more as an analytical point of reference and the event that catalyzed the Cold War, which Masuda believes had previously existed only in the popular imagination, transforming it into a reality for the people of the nations involved in the conflict. Masuda sets before himself a very ambitious task. He seeks to “rewrite the formation of the Cold War” by “synthesizing social and diplomatic history and local and global history” (p. 2). He argues that the Cold War “existed not because it was there but because people thought that it existed. It was, in this way, an imagined reality that came to be shared and solidified in the postwar era, particularly during the Korean War, which many feared was the beginning of World War III” (p. 2). For Masuda, the Cold War was a transnational phenomenon in which ordinary citizens in societies as diverse as the United States, Japan, China, and the Philippines, still haunted by recent memories of the Second World War and out of concern for the future, not only reacted to emerging East-West tensions, but actually participated in the construction of a new form of global confrontation.

Cold War Crucible is divided into three sections. In the first section, Masuda explores how events occurring between 1945 and 1950 in the United States and Japan that seemingly reflected a “coherent narrative of American Cold War strategy” (p. 37) were the result of domestic pressures. This includes the Reverse Course in Japan, which Masuda claims was “less a result of Washington's Cold War policy than part of a conservative backlash in Japan aimed at the recovery of normalcy and familiar order” (p. 37). In the second section, which follows the outbreak of the Korean War, Masuda argues that “Washington's and Bejing's policies had less to do with military strategy or Cold War thinking than with the politics of impression in attempts to dominate the currents of popular attitudes and that policy-making processes were not isolated from social politics and the daily lives of ordinary people” (p. 7). He goes to great lengths to demonstrate that many key decisions made at what have traditionally been portrayed as flashpoints in the history of the early Cold War, including the US decision to cross the 38th parallel during the Korean War and the Chinese decision to commit troops to Korea, were more products of domestic pressures than strategic calculations. Finally, in the third section, Masuda explores how actors used the new reality of the Cold War to settle local disagreements. In this section, Masuda considers, among others, the Red Purge in Japan, the White Terror in Taiwan, the suppression of counterrevolutionaries in the People's Republic of China, and McCarthyism in the United States.

Masuda's is hardly the first book to combine diplomatic history with social history. Yet, Cold War Crucible is extraordinarily well researched, drawing on an impressive array of archival materials in many languages. Masuda skillfully weaves into his narrative diplomatic and government records as well as the letters of ordinary citizens addressed to US presidents and local Chinese Communist Party offices. Masuda conducted research in dozens of archives in multiple countries, including the United States, Japan, the People's Republic of China, the United Kingdom, India, Singapore, Taiwan, and elsewhere. This is a most impressive achievement.

One could make the case that Masuda overstates the importance of domestic pressures and events at the expense of developing the narrative on diplomatic and military considerations that undoubtedly moved elites in the direction of tougher positions in the bourgeoning Cold War. This includes during the Korean War. While Masuda recognizes the need to conduct more extensive research on all societies around the world to inspect the “imagined and constructed nature of the Cold War world” (p. 6), including research on Soviet society, the general exclusion of the Soviet Union, a key player in the East-West rivalry, if only imagined, is troubling. While Masuda and others have demonstrated that the Cold War was much more than a binary conflict between the Washington and Moscow, the people of the Soviet Union were undeniably major players in its development. These minor reservations notwithstanding, Cold War Crucible is a refreshingly innovative and thought-provoking study of a period about which so much has already been written.