Ultra in the Pacific: How Breaking Japanese Codes and Ciphers Affected Naval Operations Against Japan, 1941-45 (The Secret War)

Ultra, the name given to information gained from the deciphering of messages passed by the enemy in code during the Second World War, was certainly an invaluable asset to the Allies; but its application gave rise to other problems. If the information gained was used too freely, the enemy would soon suspect that their radio traffic was being intercepted and read, and would take the necessary counter-measures. Fortunately for the Americans in the Pacific, the Japanese sincerely believed that it was not possible for Westerners to learn their language. Lulled by this misapprehension into a false sense of security, they could only ascribe to luck or coincidence the remarkable frequency with which the Americans intercepted their plans.The war in the Pacific has had many chroniclers but the secret of Ultra remained guarded for many years and only recently has it become possible to assess in detail the effect it has on the campaign. John Winton's expert analysis of the records now available are here combined with his encyclopedic knowledge of the naval history of the Second World War to tell, for the first time, what exactly the Allies did learn from Ultra in the Pacific War and to what use that knowledge was put. The result is a fascinating story told with the zest and pace one might expect from an author who is both a highly respected historian and a first-class novelist. His long-overdue tribute to Joe Rochefort, whose contribution to the successful outcome of the War in the Pacific is hard to overemphasize, is particularly welcome. An astounding assessment of the invaluable role of U.S. and Allied codebreakers in the sprawling naval war against Japan. Essential reading for fans of Liza Mundy, Ian W. Toll, and James D. Hornfischer. How did the allies intercept, decipher, and analyse Japanese secret messages through the course of World War Two? And perhaps more importantly, how were they able to use the information they gathered without highlighting to the Japanese that their codes had been cracked?John Winton has skillfully used a wealth of previously top secret American and British sources to craft an astounding history of intelligence and espionage in the Pacific War.He uncovers the key role played by codebreakers in the naval stand-off at Coral Sea and the showdown at Midway; how cryptanalysis affected the Guadalcanal campaign and set up the airborne assassination of Admiral Yamoto; ULTRAs importance in giving the US foreknowledge of Japanese operations in the Solomons and made Allied submarines such a deadly threat to enemy shipping.an illuminating view of a fascinating topic. Naval War College Reviewa very well-written general account of Allied radio intelligence operations directed against the Imperial Japanese Navy throughout World War II. The Journal of Asian Studies[Winton] is a comfortable writer who moves skillfully through the essential facts of each case study, integrating the operational elements with signals intelligence. Significantly, he includes other linked intelligence operations The Journal of Military History