U.S., Japan Extend Nuclear Agreement


The United States and Japan automatically extended a 1988 civilian nuclear pact on July 17 as Japanese officials pledged to address concerns about Japan’s substantial plutonium stockpile. The agreement allowed either side to request a review of the deal, but neither side chose to do so. Under its terms, the pact remains in force in perpetuity but each side, if it chooses, is able to terminate the agreement by giving six months’ written notice. Japan’s civilian nuclear cooperation agreement, known as a 123 agreement setting U.S. terms for sharing nuclear energy technology, is unique and controversial due to the blanket consent that it provides Tokyo to enrich uranium and extract plutonium from U.S.-origin spent nuclear fuel. Enrichment and reprocessing activities are considered sensitive because they can be used to make fuel for power reactors and produce the explosive material for nuclear weapons.

Japan had more than 47 tons of plutonium as of 2016, enough to produce around 6,000 nuclear warheads. Ten tons of this material are stored in Japan while the remainder is held in France and the United Kingdom. Critics fear that these materials could be used to build nuclear weapons, thereby granting Japan a latent nuclear weapons capability. The Nikkei Asian Review reported that prior to the pact’s extension, the United States demanded Japan make efforts to reduce the stockpile. On July 31, Japan’s nuclear energy commission adopted a guideline to cap plutonium production and eventually reduce the stockpile, but it provided no timeline or specifics on a plan to do so.—MONICA MONTGOMERY