Taiwan’s South China Sea Defense Challenge

The ROC’s two territories in the region have strategic and political significance, yet both are difficult to defend.

Taiwan’s Coast Guard in March twice conducted live-fire drills on the Pratas Islands – known in Chinese as the “Dongsha” – located in the South China Sea 450 kilometers southwest of Kaohsiung. Such exercises were rare in years past. The Pratas are tiny, without permanent inhabitants, and remote. Among territories administered by Taiwan, only Itu Aba (Taiping Island), part of the Spratly Island archipelago, is more far-flung. 

Yet the Pratas’ geography makes them vulnerable to Chinese coercion. Not only are the islets far from Taiwan, they also are flat and devoid of any natural defense positions. Beijing claims the Pratas along with almost all of the 3.5 million-square-kilometer South China Sea, where it has built many military installations. The Pratas are closer to Guangdong Province than to Taiwan – about 260 kilometers from the city of Shantou – and come within Hong Kong’s airspace.

As cross-Strait tensions spiked last year, Chinese military aircraft began routinely breaching Taiwan’s southwest air defense identification zone (ADIZ) between the main island of Taiwan and the Pratas. The People’s Liberation Army (PLA) flew 380 times into that part of Taiwan’s ADIZ last year, according to the Institute for National Defense and Security Research (INDSR), a think tank affiliated with Taiwan’s Ministry of National Defense (MND). It was the most incursions since 1996, when China fired missiles into the waters near Taiwan to intimidate voters ahead of the country’s first direct presidential election.

Graphic: Wikipedia

The Chinese military may have been collecting intelligence while testing Taiwan’s response capabilities. The relentless incursions take a toll on Taiwan’s Air Force, which usually responds by scrambling fighter jets.

Of perhaps greater importance is the signaling represented by the incursions. Alexander Huang, a professor of strategy and wargaming at Tamkang University, says the forays have a psychological impact on Taiwan’s domestic audience, as well as on political and military leadership in the U.S. To the domestic audience, the PLA appears to be flexing its muscles. The signal to Washington is that the PLA can monitor and perhaps disrupt the activity of U.S. forces in the area.

For Taiwan, the message is grim. “The PLA could take the Pratas pretty easily, even if there are Taiwan Marines stationed there,” says Grant Newsham, a senior fellow at the Center for Security Policy in Washington, DC. “They may not even need to attack; just seal the place off” with an air and sea blockade.

Occupying the Pratas would not be a military game changer for the PRC, but it would facilitate surveillance and intelligence collection. There would also be “a certain military usefulness,” Newsham says. From the islands, PLA missiles could “reach out quite a ways.”

At the same time, China could disrupt shipping routes that run through the Taiwan Strait and Bashi Channel. “China could create a choke point and control how things moved in that area,” says Roger Yee, global president of Taipei-based security consultancy Magna Imperium Consulting.

Satellite images of Taiwan-administered Pratas (Dongsha) Island. Photo: Wikipedia

The heaviest blow would be political, though, says Drew Thompson, a former Pentagon official who is now a visiting senior research fellow at the National University of Singapore’s Lee Kuan Yew School of Public Policy. “I question the strategic relevance in terms of the defense of Taiwan’s homeland of Itu Aba and Dongsha [Pratas],” Thompson says. “Kinmen and Matsu are much more relevant.” 

Satellite images of Taiwan-administered Itu Aba (Taiping Island). Photo: Wikipedia

From a political standpoint, however, losing the South China Sea territories “would be a tremendous embarrassment for the leadership [of Taiwan] and the military,” he says.

Known unknowns

Compared to the Pratas, Itu Aba looks more secure for now. China will likely approach the largest Spratly island more cautiously than the Pratas, says Tamkang University’s Huang. He notes that the area has four claimants: the Philippines and Vietnam as well as China and Taiwan. That complicates Beijing’s calculations. Further, China already has installations near Itu Aba.

That is not to say Itu Aba is devoid of strategic value. Quite the opposite, as much of Taiwan’s energy supply travels on the sea lanes near the Spratlys. Taiwan also has fishing rights in the surrounding exclusive economic zone – the area of sea that stretches 200 nautical miles from the coast of the island and grants Taiwan special rights to certain marine resources – and substantial energy reserves, such as hydrocarbons, may exist below the seabed.

In March, Defense Minister Chiu Kuo-cheng said Taiwan had beefed up its defense of Itu Aba in response to China’s aggression in the region. “My goal is for us to be ready at all times,” he told Taiwanese lawmakers.

Still, Taiwan has not deployed Marines to Itu Aba as it has to the Pratas. No military troops have been stationed there since 2000, when they were replaced with Coast Guard personnel to lower tensions in the area.

Military personnel boarding a C-130 Hercules transport aircraft on Itu Aba (Taiping
Island). Photo: Wikipedia

Taiwan dispatched Marines to the Pratas last year amid media reports that China was planning a massive military exercise on Hainan Island simulating capture of the islands. Wang Ting-yu, a Democratic Progressive Party lawmaker on the Legislative Yuan’s Foreign Affairs and National Defense Committee, told The South China Morning Post that the Marines are U.S.-trained and capable of anti-landing and anti-parachute operations.

Hong Kong-related tensions may also be affecting Beijing’s approach to the Pratas. Last August, five Hongkongers fleeing the city following Beijing’s imposition of a draconian national security law reportedly reached the Pratas by boat. Taiwan’s Coast Guard intercepted them and brought them to a detention facility in Kaohsiung.

Hong Kong Security Secretary John Lee called on Taiwan to send the individuals back to the former British colony “after going through legitimate procedures” and suggested that the five may face criminal charges in Hong Kong. “If they are suspected of committing crimes in Hong Kong, do not harbor criminals,” he said.

After that incident – and as tensions rose between the U.S. and China in the South China Sea – Taiwan deployed its domestically made Albatross drones to both the Pratas and Itu Aba. The MND told reporters that that the unmanned aerial vehicles (UAV) would enhance reconnaissance capabilities in the South China Sea and strengthen the Coast Guard’s defense of the two islets.

In October, Hong Kong air traffic controllers advised a civilian aircraft chartered by Taiwan’s military not to enter the airspace over the Pratas because of “dangerous activities” happening below 26,000 feet, according to the Civil Aeronautics Administration (CAA). The pilot of the plane, which was carrying supplies to the 250 Taiwanese Coast Guard officers stationed on the islands, eventually flew the aircraft back to Kaohsiung after the air traffic controllers would not say when the activities in question would end.

“While the increased pace of Chinese activity [near the Pratas] in the fourth quarter of 2020 might be linked to the boat departures from Hong Kong, such activity was inevitable” given Beijing’s sovereignty claim and the icy state of cross-Strait relations, says Ross Darrell Feingold, a Taipei-based political risk analyst. “It puts enormous pressure on Taiwan’s civilian leadership and national security apparatus, and might be a precursor to the establishment by China of a South China Sea ADIZ.”

According to Chinese-language CommonWealth Magazine, Taiwan’s military is prepared for a PLA attack on the Pratas. Under the “Border Defense Battle Plan,” the Navy would deploy a task force combining Navy and Marine units to carry out amphibious attacks on enemy forces occupying the islands, CommonWealth said in an August report. Reinforcements would arrive on Navy C-130 transport planes.

Beijing might opt for gray-zone tactics instead to test Taiwan’s mettle, says Tamkang University’s Huang. “They could send boats of fishermen who request to land on the islands. But it would be hard to tell if they are really fishermen.”

Beyond Taiwan’s own military readiness, the U.S. can play a critical role in deterring Chinese aggression, says Newsham of the Center for Security Policy. He notes that Washington has a wide variety of policy tools it can leverage to influence Chinese behavior.

“The U.S. would have to respond, and it can make that clear to China,” he says. “Would China want to be restricted from the global financial system? Because that’s an option the U.S. has as long as the U.S. dollar reigns supreme.”