Wars produce sudden and irrevocable changes. Although they are fought for reasons, they can stampede passions, and mass passions give no quarter to reason, let alone to any individuals barring the way. Millions of lives lost mean millions of roads not taken, altering the roster of the born and unborn, and producing decisions informed by the road taken. The passions elicited by the killing, the dying, and the witnessing put a period on the way the world was. The combustion of reason and passion leaves transformative and often unintended outcomes, which in the long term may prove more important than the war’s original purpose. Given the costs, unpredictability, and irretrievability, wars are important to understand.

We in the West treat World War II, the Second Sino-Japanese War, and the Chinese Civil War as distinct events, and in doing so we misunderstand each one. The conventional tale of World War II divides into two fronts, a European theater, opening in 1939, and a Pacific theater, opening in 1941, and the tale ends in 1945 with the fall of Berlin in May and with atomic bombs on Japan in August. Yet Japan’s war began a decade prior in 1931, and that war precipitated its attack on Pearl Harbor, which drew the United States into World War II, and thus precluded a Japanese victory in China. The conventional tale does little to explain Japan’s curious behavior. An attack on one’s most important trading partner and source of the war matériel necessary to continue the fight in China would seem remarkably counterproductive.