Over the past two weeks, a dispute between Japan and China over a series of islands claimed by both countries has spiralled into a major diplomatic incident. In response to the Japanese coastguard’s seizure of a Chinese fishing boat following a collision near the islands, Beijing has cut off high-level diplomatic talks with Japan. In both countries, nationalist protestors have taken to the streets.

The dispute is part of an ominous trend. In the late 1990s and early 2000s, China enjoyed a honeymoon of sorts with its Asian neighbours, as it emerged from the defensive crouch of its post-Mao foreign policy and began to use soft power – aid, trade deals, working with regional organisations – to deflate concerns about its rise and turn itself into, potentially, the pre-eminent regional power. The honeymoon appears to be over. In the wake of the global economic crisis, with US influence apparently fading, China has pursued a more confrontational and aggressive foreign policy. It has claimed the South China Sea as its core national interest, although parts of it are claimed by at least four other countries; it has ramped up a border dispute with India; it has largely refused to listen to Southeast Asian nations’ complaints that its dams on the upper portions of the Mekong River are destroying the livelihoods of people downstream; and it has made repeated incursions into (according to Tokyo) Japan’s territorial waters.

But the new posture could backfire. Worried about China’s aggressiveness, Southeast Asian nations this summer asked the US to take a tougher stand on the South China Sea. Hillary Clinton duly announced that the US believes an amicable resolution of claims to the sea to be in America’s core interest. Japan and the US have also boosted funding for initiatives in the Mekong River area, while the Obama administration has quietly built a close strategic relationship with both Indonesia and Vietnam. Washington has embarked on a controversial agreement to provide nuclear technology to Hanoi and may soon be conducting joint naval exercises with Vietnam. When Vietnamese officials visit Washington, China is always top of the agenda. India, which just a few years ago was talking of a new relationship with China and the emerging giants’ shared interests on climate change and trade, has fortified its border with China and pushed harder to improve relations with the US and Japan. Yet China, at least for the moment, seems unfazed.