The ASEAN Regional Forum (ARF), Asia's only regional security mechanism, is often derided as a mere "talk shop," where diplomats gather to discuss security concerns but never actually do anything about them. At this year's annual foreign ministers' meeting, which convened late last month in Hanoi, words were enough to cause a considerable stir. U.S. Secretary of State Hillary Clinton's assertion of U.S. interests in the South China Sea, and her call for the resolution of territorial disputes there have been interpreted as a direct challenge to China. Beijing's readiness to see an affront is revealing of its mentality.

The South China Sea is one of the world's strategic waterways. One-third of world shipping transits its waters, making it the second most-used sea lane in the world. Japan and its Northeast Asian neighbors depend on the traffic of goods through the area. Some 500 million people depend on the waters for their food and livelihoods. In addition to rich fishing grounds, the seabed is thought to contain huge oil and natural gas reserves.

Those riches are partially responsible for the competing claims to islands that dot the South China Sea. Six states — Brunei, China, Indonesia, Malaysia, the Philippines and Vietnam — have staked claims. China and Vietnam have clashed repeatedly over the Spratly Islands; in 1988 a battle claimed more than 70 Vietnamese lives. Rivals have built up facilities on the territories under their control — "fishermen's huts" look a lot like military facilities. The need to defend those holdings has driven defense procurement policies among claimants and it is possible to discern what looks like an arms race in the area.