According to newly declassified documents held by the U.S., Japan had considered building a nuclear weapons development program as early as the 1950s, five years after the cessation of World War II. The government chose not to move forward with the plans only because it was sure to meet opposition, so soon after the atomic destruction of Hiroshima and Nagasaki.
The documents revealed that Douglas MacArthur, then the US ambassador to Tokyo, knew in 1958 that then Japanese Prime Minister Nobusuke Kishi thought it was imperative that Japan had its own nuclear weapons. Kishi was looking towards a “defensive” nuclear capability to protect the nation from the Soviet Union as the Cold War raged. Kishi at that time had apparently argued that the constitution “did not prohibit Japan from having those kinds of weapons”.
Kishi’s proposal then is surprising, given the country’s harrowing experiences with nuclear weapons in the final days of WWII. Japan formally adopted its current anti-nuclear weapon principles of not possessing, manufacturing, and permitting nuclear weapons in Japanese territory in the 1960s, but just a few years before that, the Japanese government had seriously thought about developing them for “defensive measures”.
Hisanari Yamada, Japan’s vice foreign minister in June 1958, told MacArthur that the possibility of defensive nuclear weapons had already been brought to their meetings in the ministry. Yamada further added that within the ministry, most thought that it did “not make too much sense for Japanese not to have modern defensive weapons, including nuclear weapons, when the only potential aggressors were armed with nuclear weapons”. The system being considered was a defensive surface-to-air missile fitted with a nuclear warhead as deterrence against possible Soviet aircraft attacks into Japanese air space.
The plans never did come into fruition, as MacArthur knew that public opinion would play a big part in shaping Japan’s nuclear weapons policy. MacArthur wrote in a telegram that the possibility of Japanese nuclear weapons “raised obvious and serious emotional and psychological problems in terms of Japanese public opinion and perhaps opinion had not evolved to the point where there could be any change in present Japanese policy.”
Because of the current “no nuclear weapons” stance that Japan has taken, the nation has never deployed its own nuclear weapons. It does retain close security ties with the U.S. – and those ties have been rekindled and discussed in the past few months, given the intensifying territorial dispute with China and the unpredictable regime in North Korea developing nuclear weapons.
[ via Telegraph UK ]