Marching Orders: The Untold Story of How the American Breaking of the Japanese Secret Codes Led to the Defeat of Nazi Germany and Japan

by Bruce Lee

For the historian, the Army’s penchant for compartmentalizing everything is frustrating. Mentioned earlier is the “Bay” system that 3-US concocted. Originally, the Bays derived from three main sources, BJs, SJAs and JMAs. The BJ series included all diplomatic traffic and those of the military attachés; the series averages about fifty messages a day, only one of which “would prove Bayworthy.” The SJAs consisted of messages sent by the Japanese naval attachés