From 1899 until the American entry into World War II, U.S. presidents sought to preserve China's territorial integrity in order to guarantee American businesses access to Chinese markets -- a policy famously known as the "open door." Before the Russo-Japanese War in 1904, Americans saw Japan as the open door's champion; but by the end of 1905, Tokyo had replaced St. Petersburg as its greatest threat. For the next thirty-six years, successive U.S. administrations worked to safeguard China and contain Japanese expansion on the mainland. The Currents of War reexamines the relationship between the United States and Japan and the casus belli in the Pacific through a fresh analysis of America's central foreign policy strategy in Asia. In this ambitious and compelling work, Sidney Pash offers a cautionary tale of oft-repeated mistakes and miscalculations. He demonstrates how continuous economic competition in the Asia-Pacific region heightened tensions between Japan and the United States for decades, eventually leading to the attack on Pearl Harbor on December 7, 1941. Pash's study is the first full reassessment of pre--World War II American-Japanese diplomatic relations in nearly three decades. It examines not only the ways in which U.S. policies led to war in the Pacific but also how this conflict gave rise to later confrontations, particularly in Korea and Vietnam. Wide-ranging and meticulously researched, this book offers a new perspective on a significant international relationship and its enduring consequences.