Masanobu Tsuji (辻 政信, Tsuji Masanobu; 11 October 1902 – disappeared c. 1961) was a Japanese army officer, politician, and war criminal. During World War II, he was an important tactical planner in the Imperial Japanese Army and developed the detailed plans for the successful Japanese invasion of Malaya at the start of the war. He also helped plan and lead the final Japanese offensive during the Guadalcanal campaign.
A Pan-Asianist, Tsuji pressured Asian countries to support Japan in World War II, despite being involved in atrocities such as the Bataan Death March and Sook Ching mass killings. He meticulously planned the mass murders in Singapore and surrounding regions, personally overseeing the Pantingan River massacre. He also once cannibalized a downed Allied airman. Tsuji evaded prosecution for Japanese war crimes at the end of the war and hid in Thailand. He returned to Japan in 1949 and was elected to the Diet as an advocate of renewed militarism. Through the 1950s he worked for American intelligence alongside Takushiro Hattori. In 1961, he disappeared on a trip to Laos.
Tsuji was among the most aggressive and influential Japanese militarists. He was a leading proponent of the concept of gekokujō, (literally "the bottom overthrowing the top") by acting without or contrary to authorization. He incited the 1939 border clash with the Soviet Union and was a vehement advocate of war against the United States. According to historian John W. Dower, Tsuji was a "fanatical ideologue and pathologically brutal staff officer".
Masanobu Tsuji was born in Ishikawa Prefecture, Japan. He received his secondary education at a military academy and later graduated from the War College.
By 1934, he was active in the Army's political intrigues as a member of the Tōseiha
("Control Faction") and helped block the attempted coup d'état of the rival Kōdōha ("Imperial Way Faction"). That brought him the patronage of General and future Prime Minister Hideki Tojo and General and future War Minister Seishirō Itagaki.
From 1938 to 1939, Tsuji was a staff officer in the Kwantung Army in Japanese-occupied Mongolia. In March 1939, after the Japanese defeat at the hands of the Soviets at Changkufeng, Tsuji instigated an aggressive border policy, which triggered the Nomonhan Incident.
When the war against America and Britain started, Tsuji was on the staff of General Tomoyuki Yamashita, whose army invaded Malaya. He was largely responsible for planning Yamashita's successful landing in Malaya and subsequent campaign against Singapore. After the capture of Singapore, Tsuji helped plan the Sook Ching, a systematic massacre of thousands of Malayan Chinese who might be hostile to Japan. He is also alleged to have cannibalized an executed American flyer during the occupation of Singapore.
He was then transferred to the staff of General Homma in the Philippines. After the US surrendered there, Tsuji sought to have all American prisoners killed and encouraged the brutal mistreatment and casual murder of prisoners in the Bataan Death March. He also had many captured officials of the Philippines government executed, including by ordering the execution of Filipino Chief Justice José Abad Santos and the attempted execution of former Speaker of the House of Representatives Manuel Roxas.
After the war, Japanese war criminals were prosecuted for the Bataan Death March, Sook Ching and other atrocities, but Tsuji fled and avoided trial. Some other army officials, who had followed Tsuji's command, were charged, and two of them were executed.
Homma countermanded many of the execution orders that had been pushed through by the Tsuji clique, including the execution orders for future Philippine president Manuel Roxas who was the former speaker of the house of representatives at that time. Homma saw these execution orders as a dishonorable violation of bushido ethics. However, Douglas MacArthur held him responsible for the actions of his subordinates and he was executed while Tsuji was on the run.
In 1932, Tsuji saw action in China, and subsequently travelled as far as Sinkiang.
He served as a staff officer in the Kwantung Army in 1937–1939. His aggressive and insubordinate attitude exacerbated the Soviet–Japanese border conflicts, and helped incite the Battle of Khalkhin Gol in 1939.
After the defeat at Khalkhin Gol, Tsuji opposed any further conflicts with the Soviet Union. After their attack on the Soviet Union in 1941, the Germans urged the Japanese to join the invasion, and many in the Japanese military wanted to avenge the defeat at Khalkhin Gol. However, Tsuji was an influential advocate of the attack on the United States. General Ryukichi Tanaka testified after the war that "the most determined single protagonist in favor of war with the United States was Tsuji Masanobu." Tsuji later wrote that his experience of Soviet firepower at Khalkhin Gol convinced him not to attack the Soviet Union in 1941.
His protectors in the Army got him safely transferred to Taiwan, where he helped organize the Army's jungle warfare school. He was then assigned to the Operations Section of the General Staff, where he became a strong advocate of war with the United States and Britain. It has been alleged that in late 1941, he planned the assassination of Prime Minister Konoe if Konoe achieved peace with the United States.
Tsuji planned the Malaya campaign for General Yamashita's 25th army. It started a few hours before the bombing of Pearl Harbour on 8th December 1941, and culminated in the defeat of the British at Singapore on 15th February 1942. Following this, the Japanese army massacred thousands of Chinese civilians in Malaya and Singapore in Operation Sook Ching and Tsuji is thought to have been the planner for this war crime as well.
Tsuji planned the Japanese overland attack in New Guinea, via the Kokoda Trail. In that as in other operations, he ordered bold offensive moves, regardless of difficulties or the costs to the troops involved.
In late 1942, Tsuji went to Guadalcanal, where he planned and led the last major Japanese attack on October 23–24. After the attacks were defeated, Tsuji went to Tokyo in person to urge additional reinforcements. However, he then accepted the Navy's conclusion that nothing could get through and recommended the evacuation of the remaining troops. He impressed the Emperor with his frankness.