Japan’s Legal Readiness in the Event of Hostilities on the Korean Peninsula

Abstract

Introduction: The use of military power is a controversial issue in Japan, primarily because of the “war renunciation clause” of the Japanese Constitution. Article 9 of the Constitution imposes restrictions on the extent to which the Japanese Self-Defense Forces (SDF) can operate overseas.1 The issue of Japan’s use of armed force raised a public furor in 2015 when the new security bills were introduced as an attempt, ostensibly, to authorize the SDF to act in “collective” self-defense as a means to strengthen the U.S.-Japan alliance.2 Despite the public outcry, the new security legislation was enacted on September 30, 2015 and came into force on March 29, 2016. The new legislation aimed to enable Japan to take a “seamless response” to any international security situation that might arise.3 In accordance with the “proactive contribution to peace” policy adopted by Prime Minister Shinzo Abe, the 2015 security legislation has achieved an overhaul of the Japanese security law regime that had, over time, developed as a patchwork of technical amendments and special legislation. Nevertheless, the security law of Japan still contains many legal gaps and uncertainties that prevent Japan from harnessing the full potential of the re-interpretation of Article 9 in the contemporary security environment.4 Since the entry into force of Japan’s new security legislation, tensions in Northeast Asia have significantly increased as the Democratic People’s Republic of Korea (North Korea) conducted aggressive missile and nuclear tests in 2017, while the U.S. President Donald Trump continued to post provocative messages alluding to the possibility of resorting to military action. Any eruption of hostilities on the Korean Peninsula—whether it be a small-scale “bloody nose” attack or full-blown warfare—will test Japan’s legal readiness under its overhauled security law regime, as well as its defense capabilities and the robustness of its emergency planning. This paper examines how the U.S.-Japan alliance operates within the legal framework for the use of force in terms of both international law and Japanese security law, in the event of an outbreak of hostilities on the Korean Peninsula. 102 Strengthening the U.S.-Japan Alliance After providing a brief review of the legal and political developments relevant to tensions on the Korean Peninsula, this paper outlines the legal framework for the use of force by the SDF. It then critically examines Japan’s legal readiness to engage in combined security operations with U.S. forces, non-combatant evacuation operations, and maritime security operations in the event of hostilities on the Peninsula.