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Editor’s Note: James Kraska is professor of oceans law and policy, Stockton Center for the Study of International Law, U.S. Naval War College. The views expressed are his own.

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U.S. has called on China to stop building artificial islands in contested waters

James Kraska: U.S. should continue to challenge Chinese sovereignty claims

CNN  — 

China has been extremely active in the South China Sea. Over the past 18 months, Beijing has been engaged in an aggressive campaign to build islands on three features in the region in an apparent effort to create new sovereign territory.

So far, it has built up some 2,000 acres – the equivalent of about 1,500 football fields – worth of territory on submerged reefs and rocks. As the building has continued, the threat to freedom of navigation – including the United States – has increased. Subi reef, for example, is a submerged feature that lies some 660 miles from the Chinese coast, yet it has been transformed into a massive artificial island, apparently to accommodate a 3,000-meter airstrip that could handle the largest military aircraft.

Meanwhile, over the past six weeks, Philippine and U.S. maritime patrol aircraft have been warned away from the artificial island, as though China is claiming that its work generates a territorial sea and national airspace. U.S. Navy Adm. Harry Harris has dismissed these maritime claims as “preposterous,” while Defense Secretary Ash Carter has stated that the United States will “fly, sail, and operate wherever international law allows.”

The “United States and everyone else in the region has a stake in this” because “it gets to the question of freedom of navigation, freedom of the seas, freedom from coercion, abiding by peaceful and lawful processes,” Carter told the media on his way to Singapore for the Shangri-La Dialogue security conference. “[A]nd that is…a longstanding U.S. position, as is freedom of flying, freedom to sail.”

International law appears to support U.S. officials’ skepticism about China’s seeming territorial aspirations.

Under article 121 of the U.N. Convention on the Law of the Sea (UNCLOS), only “naturally formed” islands or rocks that are above water at high tide generate a 12-nautical mile territorial sea – there is no lawful claim of sovereignty over a submerged reef or artificial island. Despite this, on April 24, China flashed powerful lights at Philippine aircraft near Subi reef and reportedly warned it to leave Chinese “territory.”

Similarly, on May 26, a U.S. Navy P-8A Poseidon maritime patrol aircraft was scolded by Chinese authorities for entering a “military alert zone” around Subi reef, and ordered eight times to “go away quickly.

In response to such moves, Carter noted in Singapore that “turning an underwater rock into an airfield simply does not afford the rights of sovereignty or permit restrictions on international air or maritime transit,” comments that suggest China’s activity is focusing minds on the importance of freedom of navigation for the first time in years.

How will the United States respond to all this? Well, it already has – and should continue to do so.

For a start, U.S. forces continuously challenge China’s “9-dash” demarcation line claim of “indisputable sovereignty” over 90% of the water and features of the South China Sea. Warships and military aircraft of the U.S. 7th Fleet, for example, are present in the South China Sea as a matter of routine.

Second, U.S. forces already challenge China’s illegal claim to restrict military activities within the 200-nautical mile exclusive economic zone that is generated from islands under article 121(3).

Moving forward, the United States should clearly challenge China’s right to claim a 12-nautical mile territorial sea from submerged features. Under international law, the construction of artificial islands confers no right of sovereignty over neighboring waters, and the United States has made it clear that it will not respect China’s claim over international waters and airspace.

As Secretary Carter said, “The 12 nautical miles…does not pertain to features that were submerged and now are no longer submerged.”

With this point in mind, U.S. overflights and warship patrols in the region reject China’s assertion of sovereignty over any of the features. Even if Fiery Cross reef is a “rock” that generates a 12-nautical mile territorial sea, China lacks lawful title to the feature. True, any state can construct an artificial island on the high seas. But in this case, it appears that Fiery Cross reef is on the continental shelf of one of China’s neighbors.

Until the disputes over sovereignty are resolved, the United States is not bound to observe any maritime zones that might be theoretically generated from natural land area.

Late last month, Pentagon spokesman Col. Steve Warren said “freedom of navigation operations” would continue in the South China Sea, but that U.S. military aircraft do not fly directly over areas that China has claimed in the Spratly Islands, according to the Washington Post.

They should. The islands and features of the South China Sea are devoid of national maritime zones under UNCLOS until sovereignty over them is adjudicated and recognized by the international community. This fact should give China pause, and ideally would encourage Beijing to try to resolve its claims through multilateral negotiations within the framework of international law.

Of course, whether it will do so remains to be seen. That’s why the United States should work on a robust program of military partnerships in the region, including with key states such as India, Japan and Australia. That is the best way to ensure against future Chinese claims – and guarantee freedom of navigation in the South China Sea in the future.

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