What Happens if China Declared an ADIZ in the South China Sea?
"China may not find it necessary to declare an ADIZ over the South China Sea—or if it does, it may be largely restricted to non-disputed areas or be unenforced. In other words, the “sky would not fall.” The United States can help ensure that the “sky does not fall” by cutting back or ceasing all together its ISR probes targeting China’s defenses and particularly its nuclear submarines."
In November 2013, when China surprised Japan, the United States, and the world by declaring an ADIZ in the East China Sea, analysts, media, and U.S. officials warned that the “sky is falling.” In a hail of hyperbole they predicted dire consequences and warned that China may declare a similar ADIZ in the South China Sea. That was seven years ago and the sky did not fall in the East China Sea or the South China Sea and it won’t this time either. Nevertheless ‘chicken little’-like analysts and media are crying that the “sky is about to fall” in the South China Sea. But even if China does make such a declaration, it might not be destabilizing. Moreover it is U.S. actions that will in part determine whether or not it happens and its consequences.
Let’s put the situation in perspective.
The new alarm has been raised based on a “leak” from an anonymous source in the People’s Liberation Army who says that since 2010 China has been considering declaring an ADIZ encompassing the Pratas, Paracel, and Spratly groups of features. This may be so but it does not mean that such a declaration is imminent or necessarily a “game changer.”
If China declares an ADIZ in the South China Sea it may contain similar rules and regulations to the one it established in the East China Sea. This includes a controversial requirement of prior notification for foreign aircraft entering the ADIZ even if they are only transiting it and not destined for China’s territorial airspace, as well as a vague reference to “defensive emergency measures to respond to aircraft that do not cooperate…” But Japan does not recognize it and neither does the U.S. for military aircraft—and they have kinetically challenged it with relative impunity. Moreover Australia, the Philippines, South Korea, and Taiwan all require the filing of flight plans regardless of destination.
The United States objects to it because it does not follow its own model. It claims that in its ADIZ it only applies its “recommendations” of prior notification to civilian, not military, aircraft, and that they only apply to aircraft destined for U.S. territorial airspace. In practice, however, the U.S. monitors and often intercepts with fighter jets both civilian and military aircraft in its ADIZ that do not identify themselves and their destinations and the jets accompany the foreign aircraft until they change course away from its territory. This has been particularly so regarding Russian Bear bombers flying in the U.S. ADIZ off Alaska and California—regardless of whether they are flying on a course to enter U.S. territorial airspace.
China argues that its East China Sea ADIZ rules do not “affect” normal commercial traffic and that they do not interfere with freedom of overflight. Although it does have provisions for enforcement, they have not been implemented. It has only monitored and observed foreign military aircraft flying unannounced in its ADIZ—following the same practice as the United States and Japan.
Declaring an ADIZ is not in and of itself a belligerent act. First of all, an ADIZ is not a declaration of sovereignty. No country has claimed this linkage. In fact, China has said that an ADIZ is not “territorial air space” and “has nothing to do with maritime and air jurisdiction.”
Second, the establishment and implementation of ADIZs have always been unilateral and controversial. The U.S. established the precedent of an ADIZ and its rules—for itself and Japan, South Korea and Taiwan—including in parts of the South China and East China Seas after World War II. It thinks that all other nations’ ADIZs should be based on its model. But there is no international agreement to that effect.
Third, an ADIZ declaration is not necessarily destabilizing. There are several possible forms a Chinese ADIZ in the South China Sea could take and they each have different political implications.
China could declare an ADIZ out to 200 nautical miles (the extent of its Exclusive Economic Zone) off its mainland coast and the Paracel islands and possibly above Pratas and its territorial waters but not including any other disputed islands or maritime space. That should be grudgingly acceptable to most, although its enforcement may create other problems. Pratas is claimed and occupied only by Taiwan, so China could simply refer to the “One China Policy” to explain including it. The inclusion of the Paracels (also claimed by Taiwan) would of course rile Vietnam. But China has occupied all of the Paracels since 1974. Declaring an ADIZ that includes the islands would not by itself seriously alter practical reality.
As it is now, China occasionally intercepts US intelligence, surveillance and reconnaissance (ISR) aircraft over its near waters drawing U.S. protests. Therefore a China ADIZ in the South China Sea along the above lines—especially if it excluded the Paracels, or at least the excess area inside its illegal closing lines around them—would not necessarily be a ‘game changer’.
However, a Chinese ADIZ that includes some disputed Spratly features and their “adjacent maritime waters” would be alarming to other claimants and play into the U.S. narrative that China wants to control the South China Sea including its air corridors and sea lanes. But China’s claim to sovereignty over the high tide features there is just as valid—or invalid—as that of others. Moreover the Philippines already has an ADIZ that encompasses some of the disputed features—so why can’t China? Moreover, overlapping ADIZs exist in the volatile East China Sea so far without kinetic conflict.
When China declared an ADIZ in the East China Sea, it stated that “generally speaking China does not feel there is an air security threat from ASEAN countries and therefore does not feel a need for an ADIZ.” But as the frequency, capabilities and provocativeness of American ISR probes increase, China may well feel the need to protect itself against a possible threat to its national security from the air. The perceived threat of these probes—especially to its mainland defense and its retaliatory strike nuclear submarines—may eventually reach the threshold of a perceived need for an ADIZ.
China may not find it necessary to declare an ADIZ over the South China Sea—or if it does, it may be largely restricted to non-disputed areas or be unenforced. In other words, the “sky would not fall.” The United States can help ensure that the “sky does not fall” by cutting back or ceasing all together its ISR probes targeting China’s defenses and particularly its nuclear submarines.
Dr. Mark J. Valencia is an internationally known maritime policy analyst, political commentator and consultant focused on Asia. He was a senior fellow with the East-West Center for twenty-six years where he originated, developed, and managed international, interdisciplinary projects on maritime policy and international relations in Asia. He is now an adjunct senior scholar at China’s National Institute for South China Sea Studies.