Combined Fleet Decoded: The Secret History of: American Intelligence and the Japanese Navy in World War II

Combined Fleet Decoded taught me more new material regarding the Japanese navy and the U.S. Intelligence surveying that Japanese navy than I had learned in the past 15 years of reading Second World War books and watching documentary-type DVDs such as the History Channel. That is not a crack at other books, DVDs and the History Channel. Instead, it is support for the depth which Prados examines the conflict - from its genesis twenty years before Pearl Harbor right up through the hostilities. The conflict is examined in detail. For example, Prados notes that Pearl Harbor strategist Genda's inspiration for a massed carrier attack on Pearl Harbor came from watching an American newsreel in Tokyo. Quantitative support is offered throughout. He writes that Japanese Captain Tomioka's estimate based on experience in China was that a 3-to-1 ratio was necessary to ensure success against the American aircraft in the Philippines in 1941. Of course, Prados' great advantage is time. Written in 1995 (I believe), he was able to research the combined memoirs of people like Edwin Layton and Japser Holmes a decade after each had written their memoirs and after they had passed away. After comparing notes, he makes some of the most perceptive analysis of the Pacific War. For example he provides the detail to support the notion that Macarthur had as much reason to be dismissed after the disastrous events of December 7, 1941 as Husband Kimmel. Yet Kimmel was relieved and Macarthur remained. Additionally, the Japanese trained for the "Decisive Naval Battle" instead of preparing for a prolonged naval engagement and were never really to turn the tide of battle. And for that, we are thankful.

(Reviewed by Patrick L. Moore in American Bar Association National Security Law Report Fall-Winter 1998.) It is surprisingly difficult to write a review of a classic. Without putting too fine a gloss on it, Combined Fleet Decoded (`CFD") should be considered as to intelligence work what Thucydides' The Peloponnesian War is to national naval strategy, quite simply, the epitome of its kind. In it, John Prados shows how modern strategic intelligence practice and theory came of age in World War II and did so primarily in the Pacific. In terms of scope and depth of analysis, along with sheer drama and gutlevel operational practicality, it belongs on the shelf between Peter Hopkirk's The Great Game and Adda Bozeman's Strategic Intelligence and Statecraft. CFD tells the story of the most crucial military rivalry in the history of the world, that between U.S. Navy Intelligence and the Imperial Japanese Navy in the Pacific War. While conventional conceptions of the history of World War II seem to see only a European campaign rounded at the beginning by the invasion of Poland and at the end by the bombing of Hiroshima and Nagasaki (with a couple of John Wayne movies in between), in actuality it was the Pacific War which was by far and away `Amer- `ica's" war. Europe was obviously the heavyweight bout, but the war in the Pacific was our own particular war. The Pacific War, in American strategic culture is our "Odyssey" while Europe was our `Iliad." The war in Europe was Elliot Ness versus the Mafia while the Pacific was a fight between the Texans and the Comanches and culturally much more up close and personal. Japan had been planning for yogeki zengen sakusen (an offensive/defense strategy of interceptive operations) leading to a `Decisive Battle" since 1907 and America had been anticipating the struggle since 1906 with its War Plan Orange. In any event, it cannot be denied that, absent the heroic stand at Bataan. and then the victories at Coral Sea, Midway and Guadalcanal, the D-Day landings would have been drastically delayed and the European air offensive might never have gotten off the ground. What is insufficiently appreciated is that what made the early American shoestring counter-offensive against Japan and the- eventual turnaround of the war in the South Pacific possible was the vastly superior intelligence methods and organization brought to bear with typical American zeal, teamwork, ingenuity and know-how by the U.S. Navy. It was an effort which the pseudomodern military culture of Japan at the time could not even conceive of. For example, Japan never produced ship recognition models or aircraft identification flashcards-simple but indispensable training aids without which no naval air force could expect to fight a consistently proficient war. Also, it wasn't until April of 1945 that the Japanese Combined Fleet began to share intelligence materials with the Imperial Japanese Army (while the U.S. Navy and Army worked hand in hand, even if they

The detail in examining all aspects of intelligence in the Japanese and American navies during WWII -- from fleet recognition, to traffic analysis, to wartime production information, to the role of Ultra and decryption -- make Prados' book an excellent study. Those familiar with WWII issues will find lots of fresh material.Prados is wise enough to limit the topic to just naval intelligence issues, but still fills 735 pages with detail and skill. The pleasant surprise is that it's so well-written, building each issue to its climax in the wartime theater. And, with 50+ years of perspective, you can feel the tide of the war shift after Guadalcanal.The art of intelligence-gathering increased dramatically during this war because of radio intercepts, so Prados covers the topic chronologically. He has an excellent analysis of Japanese Naval strategy at Pearl Harbor, during the Pacific conquest period, and the shift to a "defensive" strategy of the homelands. Prados does an excellent job comparing the structure of Japanese and American intelligence-gathering; also in indicating both opportunities and limitations of intelligence in war-time. The reader also sees the dramatic impact that war-time propaganda has in mis-leading military leaders.Surprisingly low-tech intelligence issues are important at various points during the war: such as the absence of photo-reconnaissance early in the war for Americans. For the Japanese navy, poor ship-recognition skills by Japanese pilots and skippers leads to assumptions that American carriers present no threat because they've been reported as sunk -- or that destroyers were cruisers or even battleships.The book is closed by an excellent post-war period which does two things: follows the careers of major intelligence participants and discusses social aspects of military training.

Other reviewers have commented on the breadth of information and the contribution this book makes to our understanding of intelligence in the Pacific war. I also want to note the wonderful way it is written. Personalities, on both sides of the conflict, are fleshed out. Battles, as large as Leyte Gulf and as small as individual submarines attacks, are vividly described. The reader is made to feel the emotions of the participants. Buy the book for the information, read the book for the sheer enjoyment of it.

This is a SUPERB work on the development and uses (as well as MIS-uses) of intelligence gathering in the Pacific war in World War II. It is both in depth enough for a scholar of the era, while also being completely accessible to the relative layperson. Prados shows HOW intelligence was gathered, how the process developed, and the ways it can be (or should have been )utilized, naming names and giving praise and fault were due. It definitely belongs on ANY serious naval historians shelf