Article 9 of the Constitution of Japan

of the Japanese Constitution (日本国憲法第9条, Nihonkokukenpō dai kyū-jō^?) is a clause in the national Constitution of Japan outlawing war as a means to settle international disputes involving the state. The Constitution came into effect on May 3, 1947, following World War II. In its text, the state formally renounces the sovereign right of belligerency and aims at an international peace based on justice and order. The article also states that, to accomplish these aims, armed forces with war potential will not be maintained.

However, Japan maintains de facto armed forces, referred to as the Japan Self-Defense Forces, which may have originally been thought of as something akin to what Mahatma Gandhi called the Shanti Sena (soldiers of peace) or a collective security police (peacekeeping) force operating under the United Nations.

In July 2014, instead of using Article 96 of the Japanese Constitution to amend the Constitution, the Japanese government approved a reinterpretation which gave more powers to the Japan Self-Defense Forces, allowing them to defend other allies in case of war being declared upon them, despite concerns and disapproval from mainland China and South Korea, whereas the United States supported the move. This change is considered illegitimate by some Japanese political parties and citizens, since the Prime Minister circumvented Japan's constitutional amendment procedure. In September 2015, the Japanese National Diet made the reinterpretation official by enacting a series of laws allowing the Japan Self-Defense Forces to provide material support to allies engaged in combat internationally. The justification is that by not defending/supporting an ally, it would weaken alliances and endanger Japan.

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