The U.S.-Japan Alliance (日米同盟, Nichi-Bei Dōmei) is a military alliance between Japan and the United States of America, as codified in the Treaty of Mutual Cooperation and Security between the United States and Japan, which was first signed in 1951, took effect in 1952, and was amended in 1960. The alliance has further been codified in a series of "administrative" agreements, "status of forces" agreements, and secret pacts (密約, mitsuyaku) that have not been subject to legislative review in either country. Under the terms of the alliance, the United States undertakes to defend Japan in case of attack by a third power, and in return Japan allows U.S. military troops to be stationed on Japanese soil, and makes sizeable "sympathy payments" to underwrite the cost of U.S. bases in Japan. More U.S. military troops are stationed on Japanese soil than in any nation other than the United States. In practice, the commitment to defend Japan from attack includes extending the United States's "nuclear umbrella" to encompass the Japanese isles. The two nations also share defense technology on a limited basis, work to ensure interoperability of their respective military forces, and frequently participate in joint military exercises. Although Article 9 of Japan's Constitution forbids Japan from maintaining offensive military capabilities, Japan has supported large-scale U.S. military operations such as the Gulf War and the Iraq War with monetary contributions and dispatch of noncombat ground forces. (en)
The U.S.-Japan Alliance (日米同盟, Nichi-Bei Dōmei) is a military alliance between Japan and the United States of America, as codified in the Treaty of Mutual Cooperation and Security between the United States and Japan, which was first signed in 1951, took effect in 1952, and was amended in 1960. The alliance has further been codified in a series of "administrative" agreements, "status of forces" agreements, and secret pacts (密約, mitsuyaku) that have not been subject to legislative review in either country. (en)