Late in 1940, Tsuji, by that time a lieutenant colonel, joined the staff of the Japanese army on Taiwan. Convinced of the inevitability of war with the Western powers, he began to collect intelligence about Southeast Asia, in particular Malaya. In September 1941, Tsuji was dispatched to the staff of Japanese forces occupying French Indochina, where he stepped up his intelligence-gathering activities in anticipation of a Japanese thrust into Southeast Asia. Subsequently, Tsuji played a major role in planning the successful Japanese campaign in Malaya, culminating with the surrender of Singapore in February 1942.
After the fall of Singapore, Tsuji took part in the Guadalcanal Campaign, and in 1944, he helped plan the abortive Japanese offensive at Imphal on the Burma-India border. In Thailand when the war ended, Tsuji went into hiding, possibly to escape indictment for war crimes, until 1948. Still a right-wing nationalist, he was elected to the Japanese Diet (Parliament) four times between 1952 and 1959. Two years later, for reasons that have never been explained, Tsuji took a trip to Laos and vanished. He was pronounced legally dead on 7 July 1968.
John M. Jennings
Edgerton, Robert B. Warriors of the Rising Sun: A History of the Japanese Military. New York: Norton, 1997.; Harries, Meirion, and Susie Harries. Soldiers of the Sun: The Rise and Fall of the Imperial Japanese Army. New York: Random House, 1991.; Tsuji Masanobu. Japan's Greatest Victory/Britain's Worst Defeat. New York: Sarpedon, 1993.