As the Asia Pacific region continues to rise, competing claims and counter claims in the maritime domain are becoming more prominent. Nowhere is this more prevalent than in the South China Sea. Numerous claimants have asserted broad territorial and sovereignty rights over land features, sea space, and resources in the area. The United States has consistently encouraged all parties to resolve their disputes peacefully through a rules-based approach. The Convention is an important component of this rules-based approach and encourages the peaceful resolution of maritime disputes. Here again though, the effectiveness of the U.S. message is somewhat less credible than it might otherwise be, due to the fact that we are not a party to the Convention.

Some States in the USPACOM AOR have adopted deliberate strategies vis-à-vis the United States to try to manipulate international law to achieve desired ends. Such strategies are infinitely more achievable when working within the customary international law realm, versus the realm of treaty-based law. By joining the Convention, we greatly reduce this interpretive maneuver space of others and we place ourselves in a much stronger position to demand adherence by others to the rules contained in the Convention – rules that we have been following, protecting and promoting from the outside for many decades.

The most significant strength of international law—especially international treaty law—is its ability to establish norms of expected behavior among the community of sovereign states. This normative power of international law should not be underestimated for its ability to drive and shape the behavior of states toward stabilizing, predictable behavior. Maritime disputes in particular have benefited from the normative power of the United Nations Convention on the Law of the Sea (UNCLOS). One important normative aspect of UNCLOS was its establishment of a limit of a fully sovereign territorial sea to 12-nautical miles and creation of a 200-nautical mile exclusive economic zone. Prior to international negotiation of a final text in 1982, international claims reflected a hodgepodge of approaches. Indeed, as late as 1990, prior to the date in 1996 when UNCLOS came into force, thirteen states still claimed a 200 nautical mile territorial sea. By 2008, the normative power of UNCLOS reduced this number to seven. As of today six of these remaining seven States are party to UNCLOS, which through Article 3 explicitly limits the territorial sea to 12-nautical miles. Thus, on a global basis the number of states remaining beyond the normative reach of UNCLOS and continuing to claim a 200-nautical mile, fully sovereign territorial sea appears in fact to be only one—Peru.

In East Asia, in many ways there is a similar pattern of close conformity to the norms established in UNCLOS. China and Vietnam represent two countries that have not yet fully adopted its norms. In Vietnam’s case, its baselines remain grossly excessive. In China’s case, it too maintains numerous excessive, non-normative baseline claims, an ambiguous claim of historic or other rights within the 9-dashed line that has no basis under UNCLOS, and it remains a leaders among a small group of coastal states with non-normative perspectives on foreign military activities in the exclusive economic zone. Recent public coverage of Chinese naval activities in the exclusive economic zones of Japan and the United States suggest that perhaps this is one more way in which Chinese perspectives on international law will join the normative tide. However, even with the remaining deficiencies, both China and Vietnam are party to UNCLOS, have fully incorporated many of its other provisions into their domestic laws, and take an active part in the organizations established by this convention to further develop international law of the sea.

Third, American policy makers must realize that the contest for East Asia is one of both power and law. International law supports and legitimizes the exercise of American power. It ensures that the landscape of domestic and international opinion is favorable to american objectives, policies, and actions. International law of the sea in particular, through its assurances of freedom of navigation for security as well as commercial purposes, supports the continued nature of East Asia as a maritime system. International law regarding the free use of international airspace operates similarly. accordingly, to ensure its future position in east asia the United States should take specific actions to defend the international legal architecture pertaining to the maritime and aerial commons. acceding to the United Nations Convention on the law of the sea and once again exercising direct leadership over the development of its rules and norms is the first and most critical step. The Department of State should also reenergize its limits in the seas series to reinforce, publicly and repeatedly, international law related to sea and airspace. a good place to begin the new series would be with a detailed assessment of why international law explicitly rejects China’s “U-shaped line” in the South China Sea as the basis for Chinese jurisdiction there. others could be written to describe why China’s east China sea continental-shelf claim misapplies international law and why China’s ADIZ unlawfully asserts jurisdiction in the airspace. My sense is that East Asian states, indeed many states around the world, are desperate for active american leadership with regard to the norms and laws that govern legitimate international action.

The United States should ratify UNCLOS because doing so would further support the rules-and-norms- based international system that Washington is rightly trying to foster—in part as a means to ensure the following: (1) that neither force, nor even the threat of force, will be employed to resolve island and maritime claims disputes in a dynamic but increasingly-tense region; and (2) that such destabilizing approaches will not be encouraged anywhere else. Ratifying UNCLOS would also eliminate a perennial source of deflective criticism by China and understandable concern on the part of U.S. allies and partners. While the U.S. stance with regard to international maritime law is obviously far more sophisticated than this—including nuanced positions regarding the far-reaching applicability of customary international law— ratifying UNCLOS would nevertheless eliminate a perception that Washington is advocating “Do as I say, not as I do.” The application of maritime law in practice is shaped over time, and China is already benefitting from U.S. vulnerability in this area—vulnerability caused by not joining 166 other nations in becoming a party to UNCLOS.

I can attest from personal experience to the extent to which China has cultivated a new generation of sharp, persistent maritime legal specialists who are active in the international arena. I believe that their concerted efforts can make a difference over time, a difference that would undermine the governance of the global maritime commons to our collective detriment.