US' ambiguous stance on Sino-Japanese dispute is likely to continue despite its recent remarks and moves against China

Tensions between China and Japan over the Diaoyu Islands dispute have escalated after the recent incidents involving the two countries' vessels and planes.

As the sower of discord over the Diaoyu Islands, the United States, however, has failed to fulfill its due responsibility to defuse the tensions. Instead of taking an impartial stance, the US Senate and House of Representatives approved an amendment to the 2013 National Defense Authorization Act signed by President Barack Obama, which says "the unilateral actions of a third party will not affect US acknowledgement of the administration of Japan over the Senkaku Islands". Senkaku is the Japanese term for China's Diaoyu Islands.

At a recent joint news conference with Japanese Foreign Minister Fumio Kishida in Washington, US Secretary of State Hillary Clinton went further to say that the Senkaku (Diaoyu) Islands were under the administrative authority of Japan and the US was opposed to any unilateral action to undermine Japanese authority over the islands. She added, though, that Washington does not take a position on the islands' ultimate sovereignty. Such a stance is akin to supporting Japan's sovereignty claim over the islands, which actually belong to China.

For a long time, the US has used a stable but two-pronged approach to the Diaoyu Islands issue. On one hand, it claims that it will not take a stance on the islands' sovereignty dispute. On the other, it has reiterated time and again that the US-Japan Security Treaty is applicable to the islands, though it favors the settlement of the dispute in a peaceful manner.

It is clear that the US has been trying to send conflicting signals to China and Japan by differently stressing the two facets. Given the increasing sensitivity of the islands issue, the US sometimes becomes ambiguous on the "principle of applicability", swinging between the equivocal expression that it will adhere to its consistent stance and the explicit reaffirmation of the purview of the US-Japan Security Treaty. The remarks of different American officials are also an attempt to change the extent of Washington's intervention in the Diaoyu Islands issue.

The complicated historical background of the Diaoyu Islands issue and the importance the US attaches to its relations with both China and Japan have contributed to Washington's ambiguity.

It has become obvious that, to meet its treaty obligations to Japan, the US does not want to pledge an unconditional commitment to either party in the dispute so that it can maintain its flexible foreign policy. Such a "back-and-forth swing" approach is believed to increase the need for Washington's role in the dispute and is thus beneficial to its strategic interests in the Asia-Pacific.