Washington has made its point loud and clear in the South China Sea. But it is likely to be lost on Beijing.

“There should be no mistake: the United States will fly, sail and operate wherever international law allows,” Defense Secretary Ashton Carter declared at a late May gathering of Asia Pacific's top defense officials in Singapore. That statement came a few days after a fly-by of the US Navy's P-8A Poseidon surveillance aircraft around the man-made islands China is busy building in the South China Sea. Such actions, Carter said, demonstrate that the U.S. “will continue to protect freedom of navigation and overflight.”

Beijing, however, likely does not see the U.S. Navy's action as being aimed at upholding international law. Rather, it thinks Washington is mainly out to block its rise, a narrative that already dominates China's geopolitical consciousness.

That reading has consequences.

China has a stake in keeping the global commons open and unimpeded—a norm upon which global trade as well as the Chinese economy depend—and it could be dissuaded from attempts to restrict access to the commons if sufficient opposition can be mobilized. But if that opposition is framed around the narrative of a bipolar power struggle, it will drive the region down a zero-sum track of escalating confrontation.

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Any perception of Washington tightening the noose around China could further empower Chinese hawks. They are likely the original proponents of the reclamation projects and the strongest advocates for their militarized use and the imposition of restrictive rules to impede the mobility of the U.S. Navy. Already some in the Chinese military are making the case that the P-8A Poseidon fly-by warrants a Chinese air defense identification zone in the South China Sea.

The advance of the Chinese hardliners would confirm a suspicion rapidly gaining currency in Washington that Beijing aims to not only challenge America's position as a regional security guarantor but also subvert norms and rules that lie at the foundation of today's world order. That conclusion would also encourage the rising voices in the U.S. calling for more robust treatment of China.

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The South China Sea would then turn into the cockpit of a portentous big-power competition, a prospect every nation in the Asia Pacific dreads.

Washington needs to state and re-state that what it is determined to defend is a rules-based order, not its naval supremacy. There are many opportunities to deliver the message at the top levels: Vice Chairman of the Chinese Central Military Commission Fan Changlong is due to visit Washington this month, then there by the U.S.-China Strategic and Economic Dialogue, and an Obama-Xi Jinping meeting in September.

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But Beijing's mistrust of Washington is so deep-seated that even that will not be enough. The idea that U.S. policy is designed to contain China's rise is prevalent, politically profitable and permeates every aspect of Chinese geopolitical analysis. It will be hard to shake China from its conviction that U.S. activity in the South China Sea is a gambit to destabilize its backyard in order to enhance American alliances, enlarge the U.S. sphere of influence, and ultimately limit China's re-emergence as the region's premier power.

Other stakeholders, which include all regional nations, need to speak up in defense of rules and norms too. Some are already doing so. Australia and Japan are considering conducting their own freedom of navigation operations in the South China Sea. The Philippines has said it will continue to fly where international law allows.

But action by American allies alone is not enough, since China often dismisses them as Washington's stooges. South East Asian states, claimants or not, have a greater stake than anyone in keeping South China Sea open and free. It is incumbent on them, and significant actors like Indonesia in particular, to reach out to Beijing and make their positions known, both individually and collectively. They do not have to make their point through warships or military aircraft, nor do they have to be confrontational or engage in megaphone diplomacy. ASEAN and its members have many bilateral and multilateral means for discreet and direct communications with Beijing. And rather than issuing generic expressions of concern, they have to articulate why Chinese actions are testing freedom of navigation.

South East Asia's hesitation at confronting China is understandable in the face of the sheer asymmetry in military might, economic power and global influence. But the region may have underestimated its leverage. China does not want instability on its periphery, and nor does it wish to see frightened neighbors flock to Washington for protection. Beijing is also eager to secure regional cooperation for its Silk Road Economic Belt and 21st Century Maritime Silk Road, Xi Jinping's flagship foreign policy initiative that aims to project China's influence through its neighbourhood and as far as Europe.

Washington's recent show of resolve can give ASEAN a shot in the arm, but should not replace regional diplomacy and South East Asia's efforts at self-governance. Over-reliance on U.S. deterrence would turn regional countries' nightmare of getting caught in between two competing superpowers into reality.

Yanmei Xie is the author of a new Crisis Group report, Stirring up the South China Sea (III): A Fleeting Opportunity for Calm.

This piece first appeared in the Lowy Interpreter here. 

Image: U.S. Navy Flickr.