THE United States has been a destabilising force in the dispute between China and Japan over the sovereignty of a small chain of islands in the East China Sea. Not only did Washington create the problem in 1971 by arbitrarily returning the administrative rights of the islands to Japan, but America's claim that its security alliance with Japan applies to the tiny islands has also emboldened Tokyo to take a more aggressive stance towards Beijing.

A peaceful resolution of the issue ultimately depends on the willingness of the Japanese government to acknowledge the dispute and pursue more reconciliatory policies towards China. But a major factor is whether Washington will shift its strategy to help rein in Japan and adopt a more reasonable stance that accommodates Beijing's concerns about its maritime interests and security environment.

When Chinese-Japanese relations moved towards normalisation after Richard Nixon's visit to China in 1972, Tokyo and Beijing agreed to shelve the disagreement over who owned the islands, called Senkaku by Japan and Diaoyu by China. The situation was largely ignored for decades.

But Tokyo's decision to nationalise the islands in September 2012, prompted by the right-wing former governor of Tokyo, Mr Shintaro Ishihara, was a major change to the status quo and a violation of the tacit understanding between Beijing and Tokyo to let sleeping dogs lie. China had no choice but to react strongly: Beijing sent its patrol boats to the territorial waters surrounding the Diaoyu and has since maintained regular patrols there aimed at asserting its claim to sovereignty.

Prime Minister Shinzo Abe of Japan, a tough-talking nationalist who's been in office since December 2012, takes an uncompromising position and denies that there is any question over the islands' sovereignty. This stance, coupled with a more active security policy and other confrontational policies towards China, shows how Japan has transformed under Mr Abe into a more assertive power. This shift reminds Chinese people of Japanese aggression in the World War II era, which is a very sensitive issue in China.

The US has acted as Japan's enabler. Washington supports efforts in Tokyo to reinterpret the country's post-World War II pacifist Constitution to allow the military to act in conjunction with allies beyond Japanese territory.

Washington encourages Mr Abe to pursue a more active and assertive security policy, including the build-up of the Japanese military, which may lead to a further strengthening of Japan's already advanced air and naval forces. And Washington asserts that the US-Japan security alliance applies to the East China Sea island dispute; the US military has intensified its cooperation with the Japanese military in the area.

These policies suggest that the US, while claiming to be neutral, not only supports the Japanese position over the islands but, more importantly, prods Japan to be more aggressive towards China. Beijing feels pressure to sustain, and even step up, its patrols in the East China Sea so as to resist the combined US-Japanese power.

The immediate concern, before any long-lasting peace is addressed, is to prevent a minor clash from spiralling out of control.

Beijing and Tokyo should give their patrol boats strict guidelines on how to avoid provoking each other. The Chinese and Japanese coast guards should establish a hotline and maintain close contact, so as to avert misjudgment and escalation when an incidental conflict threatens to occur.

The two countries should strictly prohibit their citizens from landing on the islands as such actions would certainly invite like reactions from the other side.

Washington is the key to helping establish the environment for a long-term agreement, which ultimately Japan and China have to reach on their own.

In this case, for the United States, it is a matter of inaction, rather than action. Washington can help by avoiding a direct role in the dispute. It should not take sides on the sovereignty issue, nor attempt to serve as an arbitrator.

Washington should refrain from pledging overt military support to Japan as the Abe administration may regard such support as a blank cheque to take an even stronger position against China.

The most constructive thing the US could do is to use its sway to get Tokyo to officially acknowledge the sovereignty dispute.

The most efficient and realistic long-term way to solve the conflict is to reach an agreement that simply puts the sovereignty question aside. In other words, as they did in the early 1970s, China and Japan should agree to disagree, and carry on.

Japan should take the first step and acknowledge that the sovereignty of the islands is in dispute.

Were Tokyo to take this leap, Beijing could then suggest shelving the disagreement altogether.

To maintain this status going forward, Beijing and Tokyo could establish a "Three No" formula: no entry into the disputed waters, no landings on the islands, and no flight over them.

President Barack Obama's visit to Tokyo this week is an opportunity to set an agreement in motion. Short of encouraging words from Mr Obama, a Chinese-Japanese stand-off in the East China Sea is likely to continue, undermining regional stability and constraining US-China relations.

The Diaoyu islands, which are of little real strategic or economic use, are hardly worth disrupting relations among the world's three largest economies. It is time to put the issue back into a box.

NEW YORK TIMES

The writer is director of the Centre for American Studies, Fudan University, China.