Intelligence in Public Literature

Japanese Intelligence in World War II

Kotani Ken. Oxford: Osprey, 2009, 224 pages, endnotes and index. Foreword by Williamson Murray. Translated by Kotani Chiharu.

Nihongun no Interijensu: Naze Joho ga Ikasarenai no ka [Japanese Military Intelligence: Why Is Intelligence Not Used?]

Kotani Ken. Tokyo: Kodansha, 2007, 248 pages, endnotes and index.

Stephen C. Mercado

The old Italian complaint concerning the near impossibility of faithfully translating form and content from one language to another, traduttore, traditore (translator, traitor), comes to mind in reading Japanese Intelligence in World War II. Kotani Ken, an intelligence experti at the Japanese Ministry of Defense’s National Institute for Defense Studies, misidentifies his new book as the “translation” of his impressive Nihongun no Interijensu, winner of the 2007 Yamamoto Shichihei Prize for Japanese nonfiction. Rather, his new work is an adaptation of the original. In his original work, Dr. Kotani draws lessons for Tokyo’s contemporary intelligence community from the successes and failures of Imperial Japanese Army and Navy intelligence activities before and during the Second World War. Stripped of references to Japanese intelligence today, his “translation” is only an intelligence history.

In Japanese Intelligence in World War II, Dr. Kotani commits to paper a great many names of intelligence officers and organizations of the Imperial Japanese Army (IJA). He divides his IJA chapter into signals intelligence (SIGINT) and human intelligence (HUMINT) activities against the Soviet Union, China, the United States, and Great Britain, as well as the counterintelligence (CI) operations of the IJA police (Kempeitai) and the War Ministry’s Investigation Department. He also touches on the extensive collection of open sources and the valuable support given by such auxiliary organizations as the South Manchurian Railway Company and Domei News Agency. Readers will come away with a better appreciation for Japanese military intelligence, in particular for SIGINT, whose successes are almost completely unknown outside Japan.ii

The author also covers a great deal of territory in his chapter on the Imperial Japanese Navy (IJN). As in the preceding chapter, he divides his presentation into SIGINT, HUMINT, and CI activities. Readers of such books as Ladislas Farago’s Broken Seal or John Toland’s Rising Sun will be somewhat familiar with parts of this section, recognizing such names as Yoshikawa Hideo and Otto Kuehn.iii He is scathing in his criticism of the IJN for its laxity, with naval officers resistant to the notion that the enemy had broken their codes even after the defeat at Midway, the ambush of Admiral Yamamoto Isoroku by US aircraft during an unannounced visit to the front, and the temporary loss of a naval codebook in the possession of Vice Admiral Fukudome Shigeru when his aircraft plunged into the ocean near the Philippine island of Cebu.

Particularly interesting are the author’s conclusions regarding Imperial Japan’s successes and failures. He is impatient with British and American authors who dismiss Japanese military intelligence as ineffectual or emphasize their own side’s errors rather than credit Japanese capabilities. Dr. Kotani argues that capable Japanese intelligence officers suffered from insufficient resources and an inferior position relative to operations officers, who cared little for intelligence and barred them from strategic decisions. Intelligence officers contributed to such tactical successes as the naval attack against Pearl Harbor and the army airborne assault on the Dutch oilfields in Palembang but played little or no part in strategic decisions. Drawing from the memoir of Maj. Gen. Tsuchihashi Yuichi, chief of the Army General Staff’s Second Bureau (Intelligence), the author cites as an example the planning for the 1940 invasion of French Indochina. Tsuchihashi, a French expert who had served as military attaché in Paris, wrote that officers in the First Bureau (Operations) ignored his opposition to the invasion and kept him in the dark about planning for the operation. Washington’s consequent cut-off of vital oil exports to Japan sent Tokyo on a course of war and defeat.

Dr. Kotani’s “translation” generally follows the structure of his original book but ends as a simple history of the Second World War, depriving readers outside Japan of the lessons he offers in Japanese to enhance his nation’s current intelligence efforts. In his original concluding chapter, he argues for more resources, better development of intelligence officers, and more cooperation within Tokyo’s intelligence community. He notes that, never mind the resources available to Washington, Tokyo’s intelligence budget is only a third of London’s. He suggests better training and more time on target as part of a general enhancement of intelligence as a career. He favors a British “collegial” approach to develop horizontal linkages and eliminate intelligence stovepipes over a central intelligence organization in the American way. He worries that Tokyo still slights the strategic for the tactical. Warning that Japan lost the intelligence war in the Second World War not because of general intelligence failure but because of an operational failure to make use of intelligence, he suggests that Japan today develop a system to meet the challenges of an age in which the postwar US “intelligence umbrella” is in doubt.

Japanese Intelligence in World War II, apart from missing the last chapter and numerous references elsewhere in the original to contemporary Japanese intelligence issues, suffers as a “translation” from mistranslations of standard military intelligence terms and awkward English.iv Even so, Western readers should find value in this lesser version of the original Nihongun no Interijensu. It is the first general history in English of IJA and IJN intelligence activities during the Second World War.v The endnotes alone, many pointing to materials found in the British National Archives at Kew, warrant a close reading.

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iJapanese names are in traditional order, given name following family name. Kotani is also the author of Mosado: Anyaku to Koso no Rokujunenshi (2009) [Mossad: A Sixty-Year History of Covert Maneuvering and Struggle] and Igirisu no Joho Gaiko: Interijensu to wa nani ka (1999) [British Intelligence Diplomacy: What Is Intelligence?], as well as co-author of Interijensu no 20 Seki: Johoshi kara mita Kokusai Seiji (2007) [20th Century of Intelligence: International Relations Seen from Intelligence History] and Sekai no Interijensu: 21 Seki no Joho Senso wo Yomu (2007) [World Intelligence: Reading Intelligence Warfare of the 21st Century].

iiAlmost all documents of the IJA’s Central Special Intelligence Division and subordinate SIGINT units were destroyed in advance of the occupation. Fearing punishment, nearly all veterans kept their successes to themselves and highlighted failures in postwar interviews with US officials. The resulting treatment of IJA SIGINT in Anglo-American intelligence literature has been scant and skewed.

iiiYoshikawa was a naval intelligence officer operating in the guise of a clerk at the Japanese Consulate General in Honolulu on the eve of the Pearl Harbor attack. Kuehn was a German national and IJN agent in Hawaii.

ivAmong the mistranslations are the rendering of the Army General Staff’s Second Bureau (Intelligence) as “2nd Department” and the description of the Soviet Union, a hypothetical enemy, as an “imaginary” one.

vThe reviewer’s own Shadow Warriors of Nakano (2002) only concerns IJA intelligence and neglects SIGINT. Tony Matthews wrote of Japanese diplomatic intelligence activities in Shadows Dancing (1993). The reviewer is unaware of any other book-length treatments of Japanese intelligence in the Second World War.

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All statements of fact, opinion, or analysis expressed in this article are those of the author. Nothing in the article should be construed as asserting or implying US government endorsement of an article’s factual statements and interpretations.

Posted: Mar 29, 2010 10:07 AM
Last Updated: Mar 29, 2010 10:08 AM