The South China Sea - Troubled waters
Aug 6th 2012, 5:30 by Banyan | THE ECONOMIST -BEIJING

LONG a zone of contention among a number of littoral states, the South China Sea is fast becoming the focus of one of the most serious bilateral disputes between America and China. Over the weekend China’s foreign ministry summoned an American diplomat to express “strong dissatisfaction and resolute opposition” to a statement issued by the state department on August 3rd.

Tensions in the sea have mounted this year, especially between China and the Philippines on the one hand, and between China and the Vietnam on the other. Although there has not been a serious armed clash in the sea since 1988, and none is likely now, there are worries that in the current climate some low-level confrontation might escalate by accident.

The specific Chinese complaint this weekend was over America’s criticism of its recent upgrading of the administrative level of Sansha city, on one of the Paracel islands (known in China as the Xisha), from a county to a prefecture, and the establishment of a new military garrison there. In its riposte China judged its own decision to be “normal and reasonable”, though only a few hundred people live on the islets covered by the vast new maritime prefecture.

More broadly, China complains that America is taking sides in the many territorial disputes in the sea. China and Taiwan both claim virtually all the sea. Vietnam claims the Paracels, from which it was evicted by China in 1974, as well as the Spratly chain further to the south. In the south both overlap extensively with the exclusive economic zone the Philippines claims under the United Nations Convention on the Law of the Sea (UNCLOS).

Further complicating things, Malaysia and Brunei also have smaller territorial claims, and the regional club to which they, the Philippines and Vietnam all belong, the Association of South-East Asian Nations (ASEAN), has tried to play a co-ordinating and mediating role.

America insists it is entirely neutral on the territorial disputes. However China has long seen it as a troublemaker, especially since, at a security forum in Hanoi two years ago, Hillary Clinton, the secretary of state, declared the United States’ “national interest” in the affairs of the sea.

China blames America for encouraging—and perhaps even instigating—a more aggressive approach from both the Philippines and Vietnam. It asks why the American statement chose “to turn a blind eye” to what China sees as provocations by (unnamed) other countries.

This is a reference to Vietnam’s adoption of a maritime law asserting its territorial claims, and to recent disputes with it and the Philippines over fishing and the opening of disputed waters to oil and gas exploration. One reason tempers are rising is that the seas are so abundant in resources.

The most serious recent confrontation, between the Philippines and China over the Scarborough Shoal, has eased after both sides withdrew their armed patrols and competing fishing boats, as storms approached. But the Philippines says the Chinese boats left the mouth of the lagoon roped off to prevent other fishermen from entering.

The American statement backs the multilateral approach to the disputes championed by ASEAN. Its members are still smarting over their failure—for the first time in the organisation’s 45-year history—to agree on a joint statement after their annual foreign ministers’ meeting, which they held last month in Phnom Penh. It was blocked because Cambodia, a faithful Chinese client, refused to accept wording on the South China Sea demanded by some of its fellow members.

Dogged Indonesian diplomacy subsequently managed to cobble together a palatable, if bland, ASEAN position on the sea. China is working (ever so slowly) with ASEAN towards a regional code of conduct to lessen the risks of conflict. But it insists the territorial disputes are a series of bilateral issues. It does not want its smaller neighbours ganging up on it, still less if they are backed up by America.

It has a point when it says that the American statement was one-sided. And it must be suspicious that, despite its denials, America is backing its rivals’ claims. Mrs Clinton, for example, has taken to using the term “the West Philippine Sea”. It is also understandable for China to fear that America is trying to capitalise on the disputes, to cement its position in the region, in keeping with the global “rebalancing” of its military posture in favour of Asia and the Pacific.

That the American approach is broadly appreciated in the region, however, must give China pause. There are two reasons for the welcome to America. The first is the perception that China has become more strident and more of a bully in asserting its claims.

The second is that it remains unclear what those claims are based on. China couches many of its statements by reference to the islands, islets and rocks over which it claims sovereignty, and their associated waters, as if it were following UNCLOS. But it has not renounced the “nine-dashed line” (see map) which it says gives it historic rights over virtually the entire sea. China’s neighbours have reason to worry China sees their sea as its lake.