Virtual Nukes: The Formulation of Japan’s Non-nuclear Weapons Security Policy

Abstract

Informed by newly-declassified U.S. and Japanese documents, this study explains how Japan made the strategic choice to maintain its status as a non-nuclear weapons state, made possible by external and internal arrangements devised between 1964-1976. Japan obtained official and private security assurances from the U.S. ensuring its nuclear protection, preserved its material capabilities that could allow for an independent nuclear weaponization in emergencies, and simultaneously constructed public narratives that were politically justifiable to international and domestic audiences. U.S.-Japan public statements (such as Joint Communiques) and secret agreements (regarding U.S. nuclear transit rights in Japan and U.S. emergency re-entry rights in Okinawa) mutually reinforced each other, preserving U.S. deterrent capabilities in East Asia. Dual security assurances, in effect, enabled Japan to refrain from pursuing its own nuclear path. Essentially, secrecy characterized the origins of Japan’s non-nuclear weapons security policy, formulated prior to its entry into the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) framework.