Author: Craig Martin

Jus ad Bellum Implications of Japan’s New National Security Laws

[Craig Martin is an Associate Professor at the Washburn University School of Law. He specializes in international law and the use of armed force, and comparative constitutional law He can be reached at: craigxmartin@gmail.com.] Far-reaching revisions to Japan’s national security laws became effective at the end of March. Part of the government’s efforts to “reinterpret” Japan’s war-renouncing Constitution, the revised laws authorize military action that would previously have been unconstitutional. The move has been severely criticized within Japan as being a circumvention and violation of the Constitution, but there has been far less scrutiny of the international law implications of the changes. The war-renouncing provision of the Constitution ensured compliance with the jus ad bellum regime, and indeed Japan has not engaged in a use of force since World War II. But with the purported “reinterpretation” and revised laws – which the Prime Minister has said would permit Japan to engage in minesweeping in the Straits of Hormuz or use force to defend disputed islands from foreign “infringements” – Japan has an unstable and ambiguous new domestic law regime that could potentially authorize action that would violate international law. By way of background, Article 9 of Japan’s Constitution provides, in part, that the Japanese people “forever renounce war as a sovereign right of the nation and the threat or use of force in the settlement of international disputes.” It was initially drafted by a small group of Americans during the occupation, and they incorporated language and concepts from the Kellogg-Briand Pact of 1928, and Article 2(4) of the U.N. Charter that had been concluded just months earlier. Thus, Article 9 incorporated concepts and language from the jus ad bellum regime for the purpose of imposing constitutional constraints that were greater than those imposed by international law, and waiving certain rights enjoyed by states under international law. While drafted by Americans, it was embraced by the government and then the public, such that it became a powerful constitutive norm, helping to shape Japan’s post-war national identity. (For the full history, see Robinson and Moore’s book Partners for Democracy; for a shorter account and analysis, see the law review article “Binding the Dogs of War: Japan and the Constitutionalizing of Jus ad Bellum”). Soon after the return of full sovereignty to Japan in 1952, the government interpreted this first clause of Article 9 as meaning that Japan was entitled to use the minimum force necessary for individual self-defense in response to an armed attack on Japan itself. It also interpreted it as meaning that Japan was denied the right to use force in the exercise of any right of collective self-defense, or to engage in collective security operations authorized by the U.N. Security Council. These were understood to be the “sovereign rights of the nation” under international law that were waived by Japan as a matter of constitutional law. All branches of government have consistently adhered to this interpretation every since. In 2014, however, frustrated in its efforts to formally amend Article 9,