In the 1940s, China was filled with towering personalities who left behind highly quotable archives. Kurtz-Phelan, the executive editor of this magazine, has produced an intimate portrait of U.S. General George Marshall’s year-long mediation effort, launched in 1946, to stave off civil war between the Nationalists and the Communists. The book is at once a character study of the charismatic and dedicated Marshall; a narrative account of the mission’s miraculous early successes and prolonged, painful collapse; and a meditation on the impossibility of reconciling parties that are determined to remain enemies. In Kurtz-Phelan’s telling, most of the blame for the peace effort’s failure falls on the Nationalist leader Chiang Kai-shek, who refused to remedy the misrule that ultimately doomed his regime. But a deeper obstacle was Washington’s inability to uphold the mediator’s core requirement of neutrality. Both Chiang and the Chinese Communist Party chief, Mao Zedong, could see that Marshall’s true purpose was to get the Communists to accept continued Nationalist rule so that China would remain aligned with the United States. This might have been a reasonable goal if one believed the Communists could not win the civil war. But Mao did not accept that premise—and he turned out to be right.