The Pre-War Fear of Japanese Espionage: Its Impact and Legacy

How serious was the threat of pre-war Japanese espionage and clandestine operations to western interests? The question, constantly asked before 1941, was rarely addressed afterwards. Across the USA, European colonies in Asia, Australia and European capitals, the widely held belief that a sustained and well-orchestrated campaign of Japanese intelligence-gathering during the interwar years reflected Japanese covert intentions had a significant impact on official as well as popular perceptions. Given limited understanding of the wider Japanese context, a few counter-espionage successes, such as the Rutland case and code-breaking achievements against Japanese ciphers, appeared to validate the fear that Japanese espionage was a widespread threat. After 1945, investigations suggested that pre-war spy hysteria had had surprisingly little grounding in fact. This was potentially a major political embarra ssment. The impact of a disproportionate fear of espionage on the international isolation of Japan might imply at least a degree of Allied culpability in the origins of the war, and in the USA highlighted the injustice of the decision to intern JapaneseAmerican citizens. The 1988 US government apology for this failed to reveal the British evidence contributing to the security rationale behind President Roosevelt's decision: the real if poorly substantiated fear, based on the complex mix of limited known facts and widespread fantasy, over Japanese espionage that contributed to the outbreak of the second world war in the Pacific