Why US meddles in Diaoyu Islands issue?

Recently, the U.S. Senate has appended to National Defense Authorization Act for Fiscal Year 2013 the additional clause which specifies that the Article V of Japan-US Security Treaty is applicable to the Diaoyu Islands issue. It is rare an additional clause on territorial disputes between other countries is attached to National Defense Authorization Act. If the Act finally passes in the U.S. House of Representatives, it means the United States will take intervention measures or even directly deploy armed forces once China and Japan clash over the Diaoyu Islands issue.

Japanese right-wing forces have cast shadows on the Diaoyu Islands issue. Why does the United States meddle in the issue at this moment?

Originally, the U.S. public attitude toward the Diaoyu Islands is not to take side on its sovereignty. However, the Japan-US Security Treaty can be applied to the whole region of the Diaoyu Islands since Japan exercises jurisdiction over them. Obviously, the new move of the U.S. Senate does not aim to strike up the same old tune.

First, it is the requirement of U.S. foreign policies. Facing the economic downturn and the complex international situation, the United States runs short of ways to deal with too many problems. Some allies begin to doubt U.S. responsibilities, obligations and abilities. Therefore, it is imperative for the United States to establish authority and trust among its allies.

Japan is U.S. largest ally in Asia Pacific. U.S. emphasis on its responsibility of protecting Japan does not only pacify Japan but also relieve other countries in Asia Pacific which intend to rely on the United States, which is conducive to its "rebalancing" strategy in Asia Pacific.

Second, the United States intends to exert its influence on Japan's political situation. The general election has kicked off in Japan and the aggressive policy of Noda government on the Diaoyu Islands issue has been resolutely countered by China, which discourages the Japanese government and public. In order to back up Japan, the United States raises the additional clause.

Seen from the U.S. traditional strategy, the disputes between China and Japan in Asia Pacific serve interests of the United States. And the easiest way of intensifying China-Japan tensions is to incite Japanese right-wingers to stir up troubles on the surface. This U.S. move will undoubtedly increase the Japanese right-wing forces' chance to win the election.

Third, the United States focuses on the future of China-U.S. relations. Both China and the United States have just undergone change of top leadership, resulting in new situation for bilateral relations. By taking a high-profile stand on the Diaoyu Islands issue, the United States attempts to seek more room for maneuver in future China-U.S. game. However, this result of zero-sum mentality, which is purely based on interests of its own, is unlikely to end up successfully.

The Diaoyu Islands are China's inherent territory and China will resolutely safeguard its maritime rights and interests. Stable development of China-U.S .relations is conductive to peace and stability of Asia Pacific while the U.S. short-sighted and biased policies are not helpful for bilateral relations and regional stable development.