LONDON – U.S. Army intelligence officials were told that China, the Soviet Union and North Korea planned to invade Japan during the Korean War, according to documents uncovered by Kyodo News at the National Archives in London.
An unnamed source told the officials that the three countries were to attack Japan by air and submarine and that the assault would also involve an invasion of Taiwan.
The informer said Joseph Stalin, Kim Il Sung and Mao Zedong met in Moscow for around five days to formalize the plan on or around Dec. 3, 1950. They also discussed strengthening their alliance and agreed to complete their occupation of South Korea by April 1951.
The report by U.S. intelligence was passed to Britain’s military adviser in Tokyo, Brig. Gen. A.K. Ferguson, who put it in a report he sent to his bosses in London on Jan. 5, 1951.
Members of the G-2 intelligence section of the U.S. Far East Command had doubts about the plan but thought it could not be ruled out given the circumstances at the time. However, G-2 did not think any of the three countries were capable of transporting the huge number of troops by sea to invade Japan.
Korean War experts in Britain said they had never heard of a plan to invade Japan but did not think it would have been implemented. They said it might simply have been disinformation fed to the U.S. forces.
According to the source, the plan was for 500,000 Soviet troops to attack northern Japan, 500,000 North Korean soldiers to invade central Japan and 1 million Chinese troops to go into southern Japan and Taiwan.
These forces were to be aided in Japan by members of the Japanese Communist Party Youth Action Corps.
Britain’s senior representative in Japan, Alvary Gascoigne, who made some comments on the U.S. report, said it was unlikely Mao and Kim would have been in Moscow on or around Dec. 3 due to the major military offensives going on in South Korea at the time.
U.S. intelligence suspected the information could have been passed on by someone acting on behalf of the Japanese Communist Party.
“The large figures used are typical of the Communist rumor that is fed to local supporters in an attempt to boost morale by the knowledge that the ‘Great Soviet Union’ is behind them,” the G-2 section said in a document. “On the other hand, various reports are being received of Soviet intentions to attack Japan, and the possibility should not be ignored.”
Things were not going well for U.S. forces at the time the dispatch was written. On Jan. 4, 1951, Communist forces captured Seoul.
“Stalin was careful not to escalate things into a global war,” said Peter Lowe, an expert in Japanese history at England’s Manchester University. “He felt the Soviet Union would not be ready for a world war until the mid-1950s. In any case, the magnitude of invading Japan and Taiwan would have been beyond the capabilities of the Soviet Union, China and North Korea.”
The Korean War began in June 1950 when North Korea invaded South Korea.
The North Koreans were later assisted by Chinese troops, while the Soviet Union provided weapons and advice to their Communist neighbors.