I Spy

The Failure of Japanese Military Intelligence in World War II

Timothy Iles, Department of Pacific and Asian Studies, University of Victoria [About | Email]

Volume 11, Issue 1 (Book review 1 in 2011). First published in ejcjs on 31 January 2011.

Kotani, Ken (2009) Japanese Intelligence in World War II, Oxford: Osprey Publishing, x, 224 pages, ISBN 978 1 84603 425 1.

In the popular imagination, the spy is the integral, essential component of military intelligence, working alone, buried within the daily life of the 'enemy' society, transmitting information back to his supervisors with his secret radio set. In reality, of course, this figure, though romantic, is more fictional than practical. Military intelligence, especially during wartime, relies far more heavily on the interception of communications between units of an opponent's armed forces. The code-breaker, though far from glamorous, is the real operative in the task of gathering together intelligence information and making it available to 'his side'. The race to develop more intricate, secure, and flexible coding machines—such as the famous 'Enigma' machines invented and adopted in Germany in the 1910s through the end of the Second World War—led to tremendous advances in mechanical calculators, indeed paving the way for many aspects of the present-day computer. But far too often in both the popular imagination and academic research, the history of military intelligence comprises that of European or American participants in WWII and after. Relatively little work explores the conditions of Japanese intelligence-gathering during its colonial period. In order to fill in some of the gaps in scholarship on military intelligence in Japan during the years of the Pacific War, Ken Kotani's volume is a valuable and compelling publication.

Kotani divides his study into six chapters with introduction and conclusion. The chapters present a logical and comprehensive picture of Japanese wartime military intelligence, beginning with a historical overview, moving through detailed descriptions of army and navy intelligence structures and personnel, looking at the process of intelligence analysis, and finishing with an evaluation of the role of intelligence in military planning. This presentation assumes considerable background knowledge on the part of the reader related to contemporary history, both Japanese and international, especially of the years between 1900 and 1945. Kotani is not mistaken in this approach, however, given that his work targets a reader specifically interested in a particular aspect of early-twentieth century history. Assuming the background knowledge he does permits him to focus the presentation of his research on the exact subject at hand.

And quite focussed this research is, too. Despite the destruction by Japanese intelligence organisations of many tens of thousands of documents at the end of the Pacific War, Kotani has been able, through his fortuitous employment at Japan's National Institute for Defense Studies, to gain access to archives of surviving information, from which he has pieced together a solid portrait of war-era intelligence activities. Kotani discusses a range of intelligence-gathering types, from 'open source intelligence,' or 'OSINT,' such as newspapers and radio broadcasts, to 'human intelligence' or 'HUMINT' provided by agents. The special area of inquiry here, however, is that less romantic though more vital category, 'signals intelligence' or 'SIGINT.' Kotani describes the little-known successes Japanese cryptanalysts had at breaking various British, Chinese, Soviet, and American codes, and gives us a rich history of the establishment and growth of signals intelligence capabilities during the first half of the 1900s. Kotani is quite familiar with contemporary research into this aspect of Japan's colonial- and Pacific War-era, and situates his study within existing scholarship. By focussing on signals intelligence activities of the Imperial Japanese Army and Navy, his work brings much to this field that non-Japanese scholars, while not overlooking, have yet to explore with the type of thoroughness they have brought to German, American, and British activities during the First and Second World Wars. Simply as a fact-book of Japanese intelligence-gathering personnel and achievements, Kotani's work is valuable.

Yet his work provides more than a simple narrative of events and people. It is in his two final chapters that Kotani makes his biggest contribution to historical knowledge and understanding. Here, Kotani presents a compelling view that, despite having established functional intelligence-gathering agencies that in themselves were effective, the Japanese military command failed properly to appreciate the need for comprehensive, centralised intelligence analysis. The Japanese military, Kotani argues, suffered from 'a chronic shortage of excellent information analysts and civilian experts' (p. 94). The problem in essence was that 'Japanese war leaders regarded intelligence as mere information, and considered that intelligence work was a simple matter of passing information from right to left' (p. 94). This resulted in a great squandering of energy. '[A]t the strategic level, Japanese policy makers and war planners were not interested in intelligence assessments, despite the fact that they had competent intelligence services' (p. 159). It is difficult to disagree with Kotani's conclusion that Japanese intelligence gathering 'was not poor, but structural flaws meant that the efforts were often wasted' (p. 159).

In presenting this conclusion, Kotani gives us a meaningful analysis of the failings of military intelligence-processing machinery. Kotani's aim is not to lament the Japanese defeat—far from it—but to help contextualise some of the underlying reasons behind that defeat. In this his work is quite successful, although brief.

Kotani's study is to-the-point, highly readable (due in large part to the effective translation from the original Japanese by Kotani Chiharu), historically rich, and, most importantly, interesting to the general reader while still being valuable to the scholar wanting to explore the successes and failures of Japanese cryptanalysis and intelligence agencies. Intelligence in wartime, as in peacetime, is very much dependent not on information alone but on understanding. This is the message which comes through most succinctly in Kotani's work; and it is true.

About the Author

Timothy Iles is Associate Professor of Japanese Studies at the University of Victoria, British Columbia, Canada, where he teaches Japanese culture, cinema, and language. He has an MA from the University of British Columbia in Modern Japanese Literature, and a PhD from the University of Toronto, also in Modern Japanese Literature. He has taught courses on Japanese literature, theatre, culture, and cinema in Canada and the United States, and has published articles on those subjects. He is also author of Abe Kobo: an Exploration of his Prose, Drama, and Theatre (Fuccecio: European Press Academic Publishers, 2000), and The Crisis of Identity in Contemporary Japanese Film (Brill, 2008).

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