In an effort to underscore its importance to Asia, geostrategist Nicholas Spykman once described it as the ‘Asiatic Mediterranean.’ More recently, it has been dubbed the ‘Chinese Caribbean.’ And, just as Rome and the United States have sought control over the Mediterranean and Caribbean, China now seeks dominance over the South China Sea.
It’s clear that China’s claims and recent assertiveness have increased tensions in this key body of water. Yet while most attention has focused on Beijing’s appetite for fishery and energy resources, from a submariner’s perspective, the semi-closed sea is integral to China’s nuclear strategy. And without understanding the nuclear dimension of the South China Sea disputes, China’s maritime expansion makes little sense.
Possessing a credible sea-based nuclear deterrent is a priority for China's military strategy. China’s single Type 092, or Xia-class, nuclear-powered ballistic missile submarine, equipped with short-range JL-1 submarine-launched ballistic missiles (SLBMs), has never conducted a deterrent patrol from the Bohai Sea since its introduction in the 1980s. However, China is on the verge of acquiring credible second-strike capabilities with the anticipated introduction of JL-2 SLBMs (with an estimated range of 8,000 kilometres) coupled with DF-31 and DF-31A road-mobile intercontinental ballistic missiles (ICBMs). In addition, China plans to introduce up to five Type 094, or Jin-class, SSBNs outfitted with the JL-2 missiles, while constructing an underwater submarine base on Hainan Island in the South China Sea.
It’s clear, then, that China is making every effort to keep the South China Sea off limits, just as the Soviet Union did in the Sea of Okhotsk during the Cold War. Back then, the Soviet Union turned to SSBNs as insurance against US capabilities to destroy land-based ICBMs. The need to secure its insurance force from attacks, and the need for effective command and control, meant that Soviet SSBNs had to be deployed close to home, with longer-range missiles to be used to strike the continental United States. In addition to the Barents Sea, Moscow prioritized making the Sea of Okhotsk a safe haven for SSBNs by improving the physical defences of the Kuril Islands and reinforcing the Pacific Fleet based at Vladivostok. The Soviet Pacific Fleet deployed 100 submarines, combined with 140 surface warships, including a Kiev-class light aircraft carrier, to defend its insurance force in the Sea of Okhotsk.
Likewise, China needs to secure its forces in the South China Sea and modify its maritime strategy and doctrine accordingly. Currently, the primary wartime missions of the People’s Liberation Army Navy are: 1) securing sea approaches to Taiwan; 2) conducting operations in the western Pacific to deny enemy forces freedom of action; 3) protecting Chinese sea lines of communication; and 4) interdicting enemy lines of communication. With the introduction of the Type 094, protecting Chinese SSBNs will become another primary mission, and this mission will require China to kill enemy strategic antisubmarine forces and end the resistance of other claimants in the South China Sea. Chinese anti-access/area-denial capabilities, especially quieter nuclear-powered attack submarines, can be used to counter enemy forward antisubmarine warfare operations. China’s aircraft carriers, when operational, will be deployed in the South China Sea to silence the neighbouring claimants.
This strategy dates back almost two decades, to a time when China began encircling the South China Sea to fill the power vacuum created by the withdrawal of US forces from the Philippines in 1991. China reasserted ‘historical’ claims over all the islets, including the Paracel and Spratly archipelagos, and 80 percent of the 3.5 million km2 body of water along the nine-dotted U-shaped line, despite having no international legal ground to do so. Those islets can be used as air and sea bases for intelligence, surveillance, and reconnaissance activities, and as base points for claiming the deeper part of the South China Sea for PLAN ballistic missile submarines and other vessels. China also interprets the UN Convention on the Law of the Sea (UNCLOS) in an arbitrary manner and doesn’t accept military activities by foreign vessels and overflight in its waters.
Yet China's efforts to dominate the South China Sea face significant challenges. Chinese assertiveness hasn’t only inflamed hostilities from other claimants, but has also raised concerns from seafaring nations such as the United States, Japan, Australia, and India. After all, the South China Sea is a recognized international waterway, unlike the Sea of Okhotsk. In addition, since the JL-2 missiles can’t reach Los Angeles from the South China Sea, Type 094 submarines need to enter the Philippine Sea, where the US Navy and Japan Maritime Self-Defence Force conduct intense anti-submarine warfare operations.