The Debate

Is China Really About to Announce a South China Sea Air Defense Identification Zone? Maybe

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The Debate

Is China Really About to Announce a South China Sea Air Defense Identification Zone? Maybe

But maybe not.

Is China Really About to Announce a South China Sea Air Defense Identification Zone? Maybe
Credit: Keith Tarrier via

On Wednesday morning, the South China Morning Post, citing sources close to the People’s Liberation Army, reported that China may be preparing to announce an air defense identification zone (ADIZ) over the South China Sea. The SCMP doesn’t identify its source, but the source notes that the declaration would be a response to “provocative moves” by the U.S. military in the region–ostensibly referring to the U.S. practice of carrying out freedom of navigation patrols and surveillance flights in international airspace.

The report comes at a particularly sensitive time in the South China Sea. China, regional claimant states, and interested observers, including the United States, await the verdict of the Permanent Court of Arbitration in Philippines v. China. A verdict is expected later this summer. Moreover, Chinese and U.S. senior representatives are expected to meet soon for their eighth annual Strategic and Economic Dialogue. Finally, the report comes as international diplomats and security analysts converge for the Shangri-La Dialogue, a major regional security forum, this weekend in Singapore.

Moreover, these reports follow on the heel of a particularly tense month in U.S.-China activity in the South China Sea. The beginning of the month saw the third U.S. freedom of navigation operation take place in the Spratly Islands, when the USS William P. Lawrence sailed within 12 nautical miles of Fiery Cross Reef. Later in the month, a U.S. EP-3 Aries surveillance aircraft faced what U.S. officials described as an “unsafe” intercept at the hands of two Chinese fighters, the first incident of its kind over the South China Sea in nearly two years. Finally, the SCMP‘s source threatens the implementation of an ADIZ just as Chinese state media report that Beijing would increase “pressure” on the United States over maritime issues.

Analysts and observers of the South China Sea have long wrangled with the possibility that China could move to declare an ADIZ there, just like it did in the East China Sea in November 2013 (read The Diplomat‘s round-up of analysis after the declaration for more context). Tensions have risen markedly in the South China over the last two years amid international attention to China’s construction of artificial islands on features disputed by regional claimant states–including Malaysia, the Philippines, Vietnam, Brunei, and Taiwan–in the Spratly Islands. When China declared an ADIZ in November 2013, tensions were high with Japan in the East China Sea.

There are certainly several signs that point toward the eventuality of a Chinese ADIZ over the South China Sea. ADIZs require extensive infrastructure in order to be successfully enforced. China has already faced some difficulty regularly and evenly enforcing its East China Sea ADIZ. In the South China Sea, we’ve seen Beijing build two new airfields in the Spratlys, at Fiery Cross and Subi Reefs, to supplement an existing strip at Woody Island. Already, Chinese J-11 fighters have held exercises off Woody Island, where they’re now based. In its latest annual assessment of Chinese military capabilities, the U.S. Department of Defense assessed that these airstrips could host any aircraft in the People’s Liberation Army inventory. Moreover, China has sought to improve its intelligence, surveillance, and reconnaissance capabilities in the area by building advanced long-range radars and, more recently, even moving some surveillance drones to the South China Sea.

While an assessment of Chinese material capabilities may suggest that an ADIZ is forthcoming in the South China Sea, there are also reasons–primarily political and legal–to believe that Beijing may not resort to setting one up. First, China has relished in its ability to speak ambiguously about the nature of its claims in the South China Sea as it pushes forward with all sorts of material improvements to its existing holdings. Its ill-defined nine-dashed line claim is under scrutiny at The Hague. An ADIZ, while a unilateral declaration without any governing international body, would require Beijing to draw lines in the air, ostensibly reflective of what it sees to be the reality of its maritime territorial claims below. For instance, would Beijing deign to implement an ADIZ over the entirety of its nine-dashed line claim or just part? If so, why? To date, China has avoided specifying the nature of its claims, preferring instead of emphasize its dominion to nearly all of the South China Sea under a variety of convoluted historical explanations. An ADIZ might undermine this. (Even without a formal ADIZ, China has attempted to restrict free overflight by U.S. military aircraft.)

What, then, could be the purpose of periodic reports from sources close to the PLA that an ADIZ in the South China Sea is around the corner? Well, going by the comments given to the SCMP, it could be that case that the PLA source is simply seeking to deter the United States from continuing to push on with freedom of navigation patrols and surveillance flights–activities that Beijing understands to be “militarization” of the South China Sea. As one recent analysis of U.S.-China military behavior in the South China Sea suggests, Washington and Beijing may both be already playing at game of signaling with the goal of deterring behavior perceived as undesirable.

Leaving aside the question of cracking the impenetrable black boxes of what U.S. and Chinese military leaders are thinking about the prospect of a South China Sea ADIZ, we can examine what leaders have already said on the matter. On the U.S. side, the matter is simple: Washington will not accept a Chinese ADIZ over the South China Sea. Speaking in the Philippines in December 2013, a few weeks after the East China Sea ADIZ had been declared, U.S. Secretary of State John Kerry warned China:

Today, I raised our deep concerns about China’s announcement of an East China Sea Air Defense Identification Zone. I told the foreign secretary that the United States does not recognize that zone and does not accept it. The zone should not be implemented, and China should refrain from taking similar unilateral actions elsewhere in the region, and particularly over the South China Sea.

Meanwhile, China has left the door open to additional ADIZs. After the declaration of the East China Sea ADIZ in 2013, a defense ministry spokesperson noted that “China will establish other Air Defense Identification Zones at the right moment after necessary preparations are completed.” (Necessary preparations have since come a long way in the South China Sea.) Similarly, in response to a report in January 2014 by Japan’s Asahi Shimbun that China would implement a South China Sea ADIZ, Hong Lei, a spokesperson for the Chinese foreign ministry remarked that “China has all the rights to safeguard national security with any means, including establishing the ADIZ in response to the situation of air security.” Hong further said that “Chinese side has not felt any air security threat from ASEAN countries and is optimistic about its relations with neighboring countries in the South China Sea.”

Ultimately, what often seems to be left out of the will-they-won’t-they discussion regarding a South China Sea ADIZ is the utility of such a construct for China. ADIZs have their costs and benefits and Beijing should care about these. The costs are simple: China faces additional reputational damage (possibly amplified by a decision largely in Manila’s favor in Philippines v. China) and has to foot the logistical cost of enforcing an ADIZ in busy airspace over the South China Sea (all while PLA budget growth slows amid wider economic sluggishness).

The benefits of a South China Sea ADIZ? The benefits of an ADIZ are somewhat poorly understood in wider commentary on this topic in the context of the South China Sea. Broadly, ADIZs perform a sort of “early warning” function for the state that implements them. As David A. Welch has explained, “the United States declared the world’s first ADIZs to reduce the risk of a surprise attack from the Soviet Union.” States unilaterally implement these zones, asking aircraft flying through them to identify themselves and cooperate with a few regulations that are understood to provide security benefits from the implementing state as well as the aircraft flying through the zone.

Given Beijing’s vast military superiority (certainly in terms of air power), it’s unlikely that China would think to implement an ADIZ to stave off a surprise attack by some sort of fantastical unified Southeast Asian mega-air force. Just like the East China Sea ADIZ, the declaration would serve political ends, emphasizing territorial control with uncertain legality. As it saw with the East China Sea ADIZ, Beijing can expect regional states–certainly South China Sea claimant states–to avoid complying with Beijing’s rules. If the widely expected favorable result for Manila in Philippines v. China will be a loss of face for Beijing, widespread noncompliance with its South China Sea ADIZ would be doubly so.

I’ve outlined here some of the reasons why China might and might not want to implement an ADIZ over the South China Sea. No doubt, given this well-timed report from the SCMP, U.S. and Chinese officials will privately and publicly discuss this issue at the upcoming Strategic and Economic Dialogue and in Singapore, at the 2016 Shangri-La Dialogue. If China is truly planning on implementing an ADIZ in the South China Sea, the decision may have already been made, simply awaiting an announcement. If that announcement should come–perhaps later this summer or later this year–we won’t be able to say we didn’t see it coming. If the announcement never comes, perhaps everyone can focus on the more important question of reducing tensions in the South China Sea.