In , Tyler A. Pitrof presents a high-spirited revision of the US Navy’s commitment to high-steam propulsion systems, the mainstay of its World War II fleets. Pitrof’s research persuasively demonstrates that in its war against the Imperial Japanese Navy, the US Navy succeeded despite its high-steam propulsion systems rather than because of them. War with an aggressive Japan and a resurgent Germany loomed in the dark days of the late 1930s. Rear Admiral Harold G. Bowen Sr., head of the US Navy’s Bureau of Engineering, advanced a radical vision: a new fleet based on high-steam propulsion, a novel technology that promised high speeds with smaller engines and better fuel efficiency. High-steam engines had drawbacks—smaller operational ranges and maintenance issues. Nevertheless, trusting its engineers to resolve these issues, the US Navy put high-steam propulsion at the heart of its warship design from 1938 to 1945. The official record of high-steam technology’s subsequent performance has relied heavily on Bowen’s own memoir, in which he painted high-steam innovation in heroic colors. Pitrof’s empirical review of primary sources such as ship’s maintenance records, however, illuminates the opposite—that the heroism lay in the ability of American seamen to improvise solutions to keep these difficult engines running. Pitrof artfully explains engineering concepts in layman’s terms and provides an account that extends far beyond technology and into matters of naval hierarchies and bureaucracy, strategic theory, and ego. He offers a cautionary tale—as relevant to any endeavor as it is to military undertakings—about how failures arise when technical experts lack managers who understand their work. Admiral Bowen wielded excessive power because no one else in the US Navy knew enough to countermand him. Compulsively readable, is a landmark for those interested in naval history and technology but also for readers interested in the interplay between innovation, decision-making, and engineering.