Three Non-Nuclear Principles

Japan's Three Non-Nuclear Principles (非核三原則, Hikaku San Gensoku^?) are a parliamentary resolution (never adopted into law) that have guided Japanese nuclear policy since their inception in the late 1960s, and reflect general public sentiment and national policy since the end of World War II. The tenets state that Japan shall neither possess nor manufacture nuclear weapons, nor shall it permit their introduction into Japanese territory. The principles were outlined by Prime Minister Eisaku Satō in a speech to the House of Representatives in 1967 amid negotiations over the return of Okinawa from the United States. The Diet formally adopted the principles in 1971.

After the atomic bombings of Hiroshima and Nagasaki, Japanese public sentiment grew firmly opposed to the presence of nuclear weapons on Japanese soil, or even in Japanese waters. During Eisaku Satō's first term as Prime Minister, this opposition became a major obstacle to his campaign pledge to end the U.S. occupation of Okinawa, returning the island to Japanese control. The U.S. military was thought to keep nuclear weapons on the island, though it did not confirm or deny such weapons, and Satō faced opposition to reacquisition unless the nuclear presence was removed. As a compromise, Satō appeased the United States by bringing Japan into the Nuclear Non-Proliferation Treaty (NPT) in exchange for a nuclear-free, Japan-controlled Okinawa.

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