Masanobu Tsuji

CIA files declassified in 2005–2006 show that Tsuji also worked for the CIA as a spy during the Cold War. The files also acknowledged Tsuji's writings in his book Senkō Sanzenri to be mostly factual. The documents described Tsuji to be an "inseparable pair" with Takushiro Hattori and stated them to be "extremely irresponsible" and that they "will not take the consequences for their actions." Additionally, Tsuji was stated to be "the type of man who given the chance, would start World War III without any misgivings." As an asset to the CIA, he was described as having no value because of lack of expertise in politics and information manipulation.

In April 1961, he traveled to Laos and was never heard from again. It was thought that he might have been killed in the Laotian Civil War, but there were also rumors that he became an advisor to the North Vietnamese government. He was declared dead on July 20, 1968.

According to the CIA files, when Tsuji returned to Vientiane from Hanoi, he was kidnapped by the Chinese Communist Party and was being imprisoned in Yunnan, ostensibly to be used in some way to worsen Japanese-American relations or Japan's standing in Southeast Asia. Tsuji was considered to be still alive as of 8 August 1962 on the basis of handwriting analysis conducted on the writing on an envelope that was brought on 24 August 1962. However, he was never heard from again.

Additionally, the files contain information that Hattori had allegedly planned a coup to overthrow the Japanese government in 1952 that involved the assassination of Prime Minister Shigeru Yoshida and replacing him with Ichiro Hatoyama of the DPJ, but Tsuji prevented the coup by persuading the group that the real enemies were not conservatives like Yoshida but the Socialist Party. However, the files also state that the CIA learned about the attempt only after the fact and that the information was gained from an unreliable source from China. Some academics such as Tetsuo Arima of Waseda University have suggested that the entire story might have been a bluff leaked to the Chinese by Tsuji himself as a way to make him seem more influential than he actually was.

Tsuji was deeply involved in Japanese atrocities throughout the war, including the Bataan Death March and Sook Ching. He 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. In 1961, he disappeared on a trip to Laos.

In 1948, he was allowed to resign from Chinese service and returned to Japan. He began publishing books and articles about his war experiences, including an account of the Japanese victory in Malaya. He also wrote of his years in hiding in Senkō Sanzenri (潜行三千里;) "3,000 li (Chinese miles) in hiding", which became a best seller. He was elected to the Diet in 1952, and re-elected twice.

When the Japanese position in Burma collapsed in 1945, Tsuji escaped, first to Thailand and then to China, where he renewed the contacts made in Nanking. He also visited Vietnam, which was in disorder with the Viet Minh resisting the re-establishment of French rule. In China, Tsuji was both a prisoner and an employee of Chinese intelligence.

In mid-1944, Tsuji was sent to Burma, where Japanese forces had been repulsed at Imphal. Tsuji was assigned to the 33rd Army, which faced the Chinese in northeastern Burma. He was an energetic and efficient planner, if notoriously arrogant, and once helped quell panic in the ranks by ostentatiously having a bath under fire in the front lines.

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.

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 Konoye if Konoye achieved peace with the United States.

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.

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.

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.

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.

Masanobu Tsuji (辻 政信, Tsuji Masanobu, 11 October 1901 – went missing in 1961) was a Japanese army officer and politician. 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.