BEIJING -- The game has changed in the South China Sea. By sending a military aircraft to take a close-up view of the outposts China is constructing and stating it "will fly, sail, and operate wherever international law allows," the U.S. appears to have drawn a red line for Beijing.
Washington demonstrated its substantive investment in freedom of navigation and open access to Asia's maritime commons and displayed resolve to counter threats to them. The message, delivered via the Navy, will discredit a calculation by some Chinese and regional actors that the U.S. is unwilling or incapable of delivering more than verbal protests, because it is distracted by crises in other parts of the world. It may also stiffen the spines of other players, most importantly the Association of South East Asia Nations.
The U.S., however, needs to clarify its red line, bearing in mind the attendant risks. By doing so it may influence Beijing's cost-benefit calculation about how to use the outposts it is building on remote reefs and deter China from restricting access to the high seas and international airspace. Painstaking U.S. diplomacy might also bring all claimants to agree to a moratorium on island reclamation over time. "An immediate and lasting halt" to such activities, as laid down by Secretary of Defense Ashton Carter, is a much taller order, unless Washington stands ready to impose a cost on Beijing that would risk damaging bilateral relations and regional stability. Laying down a red line but failing to enforce it would cost the U.S. credibility around the world.
Washington needs to state and re-state that what it is determined to defend is the global commons, not its naval supremacy in the South China Sea. The former wins high ground in the court of international opinion. The latter may generate headlines for the grandstand wanting to see U.S.-Chinese rivalry, but it will likely result in a limited alliance and set the region down a zero-sum track.
To ensure region-wide cooperation, Washington has to ensure that its show of resolve provides a backbone to ASEAN, but does not replace it as the main body for the management of South China Sea disputes. Southeast Asian nations desire the security offered by a lasting U.S. presence but fear anything that would turn the South China Sea into a theater of big-power competition. Any unilateral deterrence and enhancement to regional alliances should be accompanied by efforts to shore up ASEAN's competence and unity. Otherwise the region's only self-governance body risks a further loss of relevance.
After delivering its warnings loud and clear through a military aircraft, Washington should allow time and space for regional diplomacy. With a shot in the arm, ASEAN may find a more assertive voice to speak with Beijing. China, with its President Xi Jinping set to visit the U.S. in September, may find incentives to tamp down tensions with Washington so as to ensure Xi has a successful visit.