International Relations and the Origins of the Pacific War examines the history of the relationship between Japan and the United States, and uses the framework of international relations theories to search for the origins of the Pacific War that erupted with Japan's attack on Pearl Harbour in 1941. Ko Unoki aims to systemize our understanding of the pivotal events that had occurred in Japan-US relations and facilitate our comprehension of their significance relating to the outbreak of the war. By using key theories in international relations and presenting the parallels that exist between current trends in the international relations of East Asia and Japan-US relations up to 1941, this work aims to provide policymakers who may use theories in analyzing world events with a source of reference and ideas.