The Chinese Air Force recently landed a number of bombers on a heavily disputed “island” in the South China Sea. The military landings follow the placement of three anti-ship cruise missiles on three islets in the Spratly Islands by China earlier this year. These moves represent yet more provocative steps in the militarization of disputed islands, rocks and low-tide elevations in the region – something that Chinese President Xi Jinping promised President Barack Obama he would not do in 2015. In response to these recent actions, the Pentagon announced that it is disinviting the Chinese military from participation in the biennial U.S. Pacific Fleet’s 20-nation “Rim of the Pacific” (RIMPAC) exercise.

Defense Secretary Jim Mattis told reporters earlier this week that China has been disinvited from the exercise because its militarization of these islands is “out of step with international law.”  And the new Indo-Pacific Commander, Adm. Philip Davidson, recently said, “China is now capable of controlling the South China Sea in scenarios short of war with the United States.”

Historically, China has declared broad maritime claims in the region based on a so-called “Nine-Dash Line” that asserts some degree of sovereignty and control over much of the South China Sea. But China’s capacious claim has a weak basis in international law and the United Nations Convention on the Law of the Sea (UNCLOS). Indeed, China’s South China Sea legal claims suffered a noteworthy blow in 2016 when the International Tribunal of the Law of the Sea (ITLOS) ruled against the bulk of China’s claims in Philippines v. China. After appearing to honor the spirit and contours of the ruling for a while, China has since changed course, asserting that the tribunal lacks jurisdiction to settle such matters.

In the absence of a clear mechanism to enforce the ITLOS-ruling and penalize Chinese aggression, China has rapidly built artificial islands and military infrastructure on numerous contested islands, rocks and so-called low-tide elevations in the region. Other nations – to include the Philippines, which has a longstanding mutual defense treaty with the U.S. – have also made claims in the South China Sea. But they all lack China’s capability (and chutzpah) to follow through. Today, international law and freedom of navigation norms are slowly giving way to the law of raw power and control. And China appears to be winning.

China’s continual disregard of the ITLOS-ruling and international, more generally, could have dire long-term consequences for the rule of law in the region. Complicating matters, the Chinese buildup has been overshadowed by negotiations with North Korea and ongoing trade disagreements between China and the U.S. China is, by far, North Korea’s biggest trading partner and food source. China’s cooperation is crucial to any worldwide efforts to contain the North Korean nuclear threat. Further, the U.S. and China remain locked in increasingly high-stakes trade negotiations.

The U.S. has repeatedly stated that it takes no position on competing sovereignty claims in the South China Sea and its underlying objective is a peaceful settlement of territorial disputes in the region. But the U.S.’s ability to influence outcomes is hampered by two realities: the U.S. is not itself a claimant in the region (a fact that China is quick to point out), and the U.S. is one of the few countries in the world that has not ratified the UNCLOS treaty – although it has consistently treated the navigational provisions as binding customary international law.

Despite not being party to UNCLOS, the U.S. has played a critical and historic role in ensuring freedom of navigation throughout the South China Sea and the world. The U.S. Navy has served as the maritime watchdog of a rules-based order on the sea for much of the 20th century. Indeed, the Navy’s very mission is linked to the maintenance of freedom of the seas. Today, an estimated 3.4 trillion dollars worth of trade flows through the South China Sea alone. Stopping this flow or restricting trade in other ways would have negative consequences for the world economy and truly catastrophic consequences for nearby nations’ economies.

In response to China’s excessive maritime claims, the U.S. military has refused to back down. U.S. forces have stepped up freedom of navigation operations (FONOPS) in the South China Sea. Just last weekend, two Navy warships conducted a freedom of navigation exercise in the vicinity of Woody Island in the Paracel Island chain. This is the same island on which Chinese bombers conducted military exercises earlier in the month. The U.S. has also conducted several FONOPS (to include four in five months) since President Donald Trump took office. This follows four other FONOPS in the South China Sea during the Obama administration. There remain open questions about the actual effectiveness of such operations and their long-term ability to deter Chinese build-up in the region. In the meantime, it seems clear that the Chinese build-up of the South China Sea (military and otherwise) will continue, as will freedom of navigation operations by the U.S. In light of these trend lines, where do we go from here?

First, we should accept the reality that China and U.S. forces will operate in the region in greater numbers, increasing the risk of an operational mishap between the two militaries. We should build upon earlier efforts to facilitate military to military communication and alleviate any risk of a China-U.S. operational mishap – a black swan-type event that could shatter peace and stability in the region.

Recall that in 2001 a U.S. Navy EP-3 surveillance plane collided with a Chinese fighter jet in the region – an incident that greatly increased tensions between the two nations. We should clarify that the existing U.S.-China Memorandum of Understanding regarding air maritime encounters applies to freedom of navigation operations in the region and provide a legal mechanism for non-compliance. Any and all steps to improve communication and ease tension between the two militaries should be pursued. While China is not participating in the upcoming RIMPAC exercise, we should remain steadfast in finding ways to “operationalize” the 2014 Code for Unplanned Encounters at Sea (CUES) in the South China Sea. CUES is designed to reduce the chance for an incident at sea between the 21 countries that have signed on to this agreement.

Second, the U.S. should continue to request that other navies conduct similar FONOPs in the South China Sea, particularly neighboring non-claimant nations. All nations benefit from a rules-based maritime system, so why shouldn’t other nations chip in? And the failure to persistently object to China’s militarization of the region and disregard of the ITLOS-ruling only serves to embolden China and provide some semblance of legitimacy to their claims. Passivity comes with its own costs.

Too often, the South China Sea narrative pits a rising China against the United States. That’s not particularly helpful. Other nations – particularly those that rely upon the South China Sea for the bulk of their trade – would stand to lose if China were allowed to disregard international law and continue its de facto dominion over the region. Australia and India are natural partners to assist with this effort. The British Navy lacks the power projection force that it once had, but it has endorsed the U.S. FONOP-approach in the South China Sea and will be conducting its own FONOP in the region later this year. Even better, a coalition-based freedom of navigation exercise of two or more countries would demonstrate a unified front against excessive Chinese maritime claims.

Third, the increasingly tense South China Sea situation once again reinforces the need for the U.S. Senate to provide its advice and consent to UNCLOS, the so-called “Constitution of the Seas.” The U.S. routinely stresses the importance of relevant UNCLOS provisions when making legal arguments for Chinese compliance with international law in the region. Indeed, Secretary Mattis did just that when criticizing Chinese militarization in the region.  But the U.S. is not a party to UNCLOS, the governing international legal framework designed to settle maritime disputes.  China, in turn, is quick to remind the U.S. of its non-party status. A diplomatic stalemate often ensues. This back and forth will likely unfold at the Shangri-La dialogues to be held this weekend.  While there are no immediate plans for the Senate to take up UNCLOS ratification, it should. It would remove an enormous distraction in the “battle of talking points” and would only bolster U.S. credibility when debating the finer legal points of UNCLOS. We should remove that barrier.

The U.S. remains the only coastal state in the world that is not party to UNCLOS (168 nations in total are parties) due to a small but vocal group of Republican senators who assert that ratifying UNCLOS would cede U.S. sovereignty to an unaccountable international organization.

These three actions alone will not by themselves dramatically alter the security landscape in the South China Sea, but we need to begin somewhere to alter the current worrying trend lines. Ultimately, the South China Sea is in need of international leadership and broad and creative diplomatic solutions. Absent this, the law of raw power and control will define the South China Sea’s future. And that future increasingly favors China.

Image: The USS John S. McCain conducts a routine patrol in the South China Sea, Jan. 22, 2017. Photo: U.S. Department of Defense