| Abstract: | Soon after the termination of the Anglo-Japanese Alliance in 1921, Squadron Leader Frederick Joseph Rutland covertly offered the Japanese navy technical help to develop aircraft carriers. In doing so Rutland played a significant role in the evolution of Japan's offensive capability that made the attack on Pearl Harbor possible. Of as lasting importance was the impact the case had in shaping the perception of ‘the Japanese threat’. British security and intelligence agencies' knowledge of Japanese naval intelligence actions in accepting this ‘offer of service’ and running Rutland as a clandestine agent was not balanced by any understanding of the fragmented nature of the Japanese leadership and intelligence bureaucracy. The case in the 1920s provided the Security Service and SIS with the apparent evidence to justify reassessing Japan from benign if opportunistic former ally to hostile power, apparently proving that Japan's intelligence actions reflected sustained hostile intent throughout the inter-War period. |
