Thai-Japanese Relations at the Start of the Pacific War: New Insight into a Controversial Period

Thailand's relations with Japan during the months surrounding the outbreak of the war in the Pacific are a topic of controversy in Thai historiography; and despite a growing number of studies which have endeavoured to explain, or at least shed light on, the rapid shift in Thai policy from neutrality on 8 December 1941 to an alliance and then declaration of war on the side of Japan by 25 January 1942, little progress or development in the debate has taken place over the decades since the war. This unsatisfactory situation has been largely due to the very limited knowledge available about the diplomatic activities that took place between Thailand and Japan during the period in question. The bulk of our information to date has come from records and recollections of Thais and Europeans involved in the events, and this has concentrated almost entirely on the activities and interplay of Thais and Europeans. The result has been to relegate Japan's presence in events of the period to some dimly perceived undertakings conducted by sinister characters who were nothing more than Thailand's enemies bent on absorbing that country into Japan's new East Asian order. The following article is an effort to redress this imbalance somewhat by directing attention toward Thai-Japanese relations. I have relied greatly on a number of dispatches that passed between Bangkok and Tokyo during the autumn of 1941. Some of the most important of these are available only from “Magic”, the files of intercepted and deciphered Japanese diplomatic messages accumulated by the United States government. The Japanese Foreign Ministry archive files on diplomatic correspondence with Thailand are extremely incomplete, and none of the messages I used from “Magic” are contained in the Japanese files.