On Wednesday, General Joseph F. Dunford Jr., chairman of the Pentagon’s Joint Chiefs of Staff, remarked that despite assurances that there would be no moves to militarize the South China Sea, China had built “10,000-foot runways, ammunition storage facilities” — and routinely deployed aviation and missile defense capabilities. U.S. naval vessels operating in East Asia report being shadowed and harassed by China’s maritime forces. The Royal Australian Navy flagship Canberra also reported a recent encounter in the South China Sea while trailed by a Chinese warship: Its helicopter pilots were hit with lasers from what appeared to be fishing vessels.

To put these and other recent events in context, I reached out to two experts: Andrew S. Erickson, a professor at the Naval War College’s China Maritime Studies Institute (CMSI) and a visiting scholar at Harvard University’s Fairbank Center for Chinese Studies, and Ryan D. Martinson, a researcher at CMSI. They are the editors of the book “China’s Maritime Gray Zone Operations” (U.S. Naval Institute, 2019). What follows is a lightly edited transcript of our conversation:

Jessica Chen Weiss: The trade war has dominated headlines in U.S.-China relations, but what’s the state of play between the United States and China in the South China Sea? How has China’s artificial enlargement of islands and reefs affected U.S. operations and interests?

Andrew S. Erickson and Ryan D. Martinson: While tariff disputes dominate world news, territorial disputes in the South China Sea remain a key flash point in U.S.-China relations. Beijing maintains a claim to all of the space within a “dashed line” enclosing most of the South China Sea — including hundreds of tiny islands and reefs. China also believes it has the right to engage in military, scientific and economic activity anywhere within this zone, and to limit at least some these same activities by other countries. Over the last decade or so, Beijing has vigorously asserted these claims. Instead of using its navy, it has relied on coast guard and maritime militia forces, operating in the “gray zone” between war and peace.

The biggest losers in China’s maritime gray zone campaign have been China’s neighbors. In 2012, Beijing succeeded in wresting a disputed feature from the Philippines. This was also a very big deal for the United States — the Philippines is a treaty ally. China’s coercion at sea also directly threatens U.S. interests in maritime freedom. Under international law, naval vessels can freely operate anywhere outside of the territorial sea. China rejects that consensus and periodically harasses U.S. Navy vessels for exercising these rights.

U.S. interests in the South China Sea range from very specific concerns about freedom of navigation to much broader concerns about the diminution of U.S. influence in a strategically vital region. The U.S. Navy helps defend these interests, patrolling the South China Sea to demonstrate Washington’s support for its allies and partners. These patrols are sometimes punctuated by “freedom of navigation operations” — actions designed to challenge China’s excessive claims.

The most significant recent development is China’s construction of enormous new facilities on the seven features that it occupies in the Spratly Archipelago. A few years ago, these were tiny outposts with zero combat power — with perhaps a few dozen soldiers who could barely keep their feet dry. Since 2013, China has transformed them into gigantic bases, some with air stations able to accommodate advanced fighters and bombers.

Last year, China installed missiles capable of sinking warships and shooting down aircraft hundreds of miles away. Given the power advantages that China already possesses compared with other South China Sea claimants, the only plausible logic for constructing these bases was to alter the military balance of power with the United States. Naturally, these new bases have become a huge source of tension between the United States and China.

JCW: The U.S. Navy recently warned that it would treat Chinese coast guard and paramilitary vessels the same as the Chinese navy. What’s behind this development?

ASE/RDM: The U.S. Navy recognizes that China has not one but three sea forces, which act increasingly in coordination. Within that division of labor, China’s navy has sought prestigious engagement and substantive learning opportunities with the U.S. Navy as Beijing’s “good cop” at sea, while China’s coast guard and maritime militia “bad cops” bully its neighbors over disputed features and waters and harass the U.S. Navy’s own ships. But now the days of Washington letting Beijing have it both ways are over.

U.S. officials have been making similar statements for months now — then-Defense Secretary Jim Mattis in November called for China’s maritime militia to “operate in a safe and professional manner in accordance with international law.” Assistant Defense Secretary Randall Schriver made a similar statement in a December interview. Their statements built on reports from the Pentagon and other agencies that exposed the maritime militia’s military nature and activities. These efforts to treat China’s three sea forces holistically and oppose their gray zone expansionism draw substantially on research conducted at CMSI over the past five years.

3. China has pursued a variety of coercive, competitive activities short of using force in the South China Sea. Which of these “gray zone activities” will the United States be more likely to succeed at deterring, and which will the United States probably have to live with?

ASE/RDM: That’s a great question, and one that Michael Mazarr addresses in our new book. Not every element of China’s maritime gray zone campaign threatens vital U.S. interests. The U.S. government clearly does not feel responsible for protecting Vietnamese fishermen in the Paracels, which Beijing has controlled since 1974. However, the U.S. does have a vital interest in deterring China from taking control of any more features occupied by the U.S.-allied Philippines. China’s seizure of Scarborough Reef in 2012 probably could have been avoided had Washington played a more active, determined role before and during the crisis.

In 2014, it looked like China might try to annex another Philippine-occupied feature — Second Thomas Shoal. The U.S. took a much more proactive approach and may have convinced Beijing to stand down. Washington has demonstrated the capacity to deter Beijing from limiting freedom of navigation in the South China Sea and is poised to continue doing so. It has likewise continued to deter China from dredging and building even the smallest of installations at Scarborough.

China uses coercion to dissuade other states from enforcing their legitimate rights and interests within their own coastal waters. A 2016 court decision completely nullified the nine-dash line as a basis for China’s maritime claims. That means China unequivocally has no right to prevent the Philippines from exploiting seabed resources within 200 nautical miles of its coast — or any reason to harass Philippine fishermen plying these same waters. This applies to other countries bordering the South China Sea. The results of the 2016 decision can help Washington consider ways of helping its allies and partners defend their coastal-state rights from China’s maritime gray zone actions.

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