Japan’s plutonium surplus, its history, and its danger
Japan’s Plutonium Overhang, Wilson Center, Nuclear Proliferation International History Project Jun 7, 2017 By William Burr Plutonium, a key element of nuclear weapons, has been an issue in U.S.-Japan relations for decades. During the administration of Jimmy Carter, the Japanese government pressed Washington for permission to process spent reactor fuel of U.S. origin so that the resulting plutonium could be used for experiments with fast breeder nuclear reactors. The government of Japan wanted to develop a “plutonium economy,” but U.S. government officials worried about the consequences of building plants to reprocess reactor fuel. According to a memo by National Security Council staffer Gerald Oplinger, published for the first time by the National Security Archive and the Nuclear Proliferation International History Project, the “projected plants would more than swamp the projected plutonium needs of all the breeder R&D programs in the world.” That “will produce a vast surplus of pure, weapons grade plutonium … which would constitute a danger in itself.” Indeed, as a result of reprocessing activities since then, Japan possesses 48 tons of plutonium and could be producing more, with no clearly defined use, when a new reprocessing facility goes on line in 2018………
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- The risk of nuclear of proliferation was a significant element in Jimmy Carter’s presidential campaign, which raised questions about the hazards of nuclear energy and attacked the Ford administration for ignoring the “deadly threat posed by plutonium in the hands of terrorists.” Not long after his inauguration, Carter signed
Presidential Directive 8,-which declared that “U.S. non-proliferation policy shall be directed at preventing the development and use of sensitive nuclear power technologies which involve direct access to plutonium, highly enriched uranium, or other weapons useable material in non-nuclear weapons states, and at minimizing the global accumulation of these materials.”
When NSC staffer Gerald Oplinger wrote that the plutonium surplus would constitute a “danger in itself,” he probably assumed an environmental hazard and possibly a proliferation risk and vulnerability to terrorism. He did not mention the latter risks, although the reference to surpluses of “weapons grade” material evoked such concerns. While Japanese reprocessing plants would be producing reactor-grade plutonium, it nevertheless has significant weapons potential. On the question of Japan’s nuclear intentions, the documents from this period that have been seen by the editor are silent; it is not clear whether U.S. officials wondered whether elements of the government of Japan had a weapons option in the back of their mind. Any such U.S. speculation, however, would have had to take into account strong Japanese anti-nuclear sentiment, rooted in terrible historical experience, Japan’s membership in good standing in the nonproliferation community, and that since the days of Prime Minister Sato, the “three Nos” has been official national policy: no possession, no manufacture, and no allowing nuclear weapons on Japanese territory. According to a 1974 national intelligence estimate, Japan was keeping “open” the possibility of a nuclear weapons capability and had the resources to produce weapons in a few years, but the intelligence agencies were divided over the likelihood of such a development. The CIA, State Department intelligence, and Army intelligence saw such a course of action as highly unlikely without a collapse of U.S. security guarantee and the emergence of a significant threat to Japan’s security.
Sources for this posting include State Department FOIA releases as well as recently declassified records at the National Archives, including the records of Gerard C. Smith and Secretary of State Edmund Muskie. Many documents on Japan from the Smith files are awaiting declassification review.
Documents in this release:…..https://www.wilsoncenter.org/publication/japans-plutonium-overhang
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