Can the Treaty on the Prohibition of Nuclear Weapons Protect Japan?
Policy Briefs

Can the Treaty on the Prohibition of Nuclear Weapons Protect Japan?

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In this policy brief, Toshio Sano examines the Treaty on the Prohibition of Nuclear Weapons (the Prohibition Treaty), which rejects the concept of nuclear deterrence. If Japan accedes to the Treaty, it will be required to withdraw from the US extended nuclear deterrence, also known as the nuclear umbrella. This nuclear umbrella serves as a crucial element of Japan’s security policy and ensures its protection in the challenging security environment of Northeast Asia. Consequently, adopting the Prohibition Treaty is not a viable policy option for Japan at present. However, lessons can be drawn from the various challenges that have emerged alongside the Prohibition Treaty, and the legitimacy of the NPT (Treaty on the Non-Proliferation of Nuclear Weapons) should be maintained to ensure the balanced implementation of its three pillars: nuclear disarmament, nuclear non-proliferation, and the peaceful use of nuclear energy.


About the Author

Toshio Sano was appointed as a Commissioner of the Japan Atomic Energy Commission (JAEC) in December 2017, and reappointed in December 2020. Before the appointment to the commissioner, he had developed his career in the diplomatic circle since his entering into the Ministry of Foreign Affairs (MOFA) in 1977, and had gained considerable experience on the issues related to non-proliferation and the international cooperation in energy policy in the diplomacy. Specifically, he was a Vice- Chair of 2015 Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons. His former postings include the Ambassador to the Conference on Disarmament in Geneva from 2013 to 2017, the Ambassador to the Kingdom of Denmark from 2010 to 2013, and Director-General of Disarmament, Non-proliferation and Science Department of MOFA from 2008 to 2010.

This policy brief is a revised version of an article that was originally published by Shinzansha in April 2022:

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Image: Hiroshima Peace Memorial Park (Wallpaper Flare)