The many factors that led to Japan's participation in World War II, and the horrifying battles that resulted, come into focus in Japan's War: The Great Pacific Conflict. The book, which takes into account Japanese and Asian documents and scholarship in addition to American and European sources, chronicles events in the Pacific from 1853 to 1951. During those years, the leaders of Japan, believing in the superiority of their nation and culture, sought to dominate East Asia and the Pacific Basin. That period also saw Japan and America becoming entangled in each other's national affairs, starting when Commodore Perry's ships ended Japan's isolation policy, and continuing into the occupation by the U. S. Army following the war.

Author Hoyt shows conflicting personalities and historical context that led to the rise of Japanese militarism and wars with China and Russia. Japan's War examines the decisions that led to the attack on Pearl Harbor, and the escalating climate of violence that resulted in the Rape of Nanking and the Bataan Death March.