Between 1954 and 1963, President Ngo Dinh Diem, against great odds but with U.S. assistance, built a functioning South Vietnamese state. But gravely misled by American journalists in Saigon, the U.S. embassy, in league with second-tier members of the State Department, urged certain South Vietnamese generals to stage a coup against Diem, resulting in his brutal murder. Despite the instability after Diem's murder, the South Vietnamese Army performed...