While China’s unilateral declaration of an air defense identification zone (ADIZ) over disputed waters in the East China Sea (ECS) caught many by surprise, today’s debate circles around the likelihood that Beijing might take the same action over the South China Sea (SCS). In its pursuit of maritime primacy in Northeast Asia, China has strayed far from the international norms that dictate the implementation and use of an ADIZ.
An ADIZ is an airspace beyond a country’s sovereign territory within which the state requires the identification, location, and air traffic control of aircraft in the interests of national security. The mechanism is a legacy of the Cold War, having first been declared by the U.S. in 1950. More than 20 states now administer their own ADIZ.
According to the Chinese Ministry of National Defense, when entering the zone, such as the one declared over the ECS, all aircraft are required to identify themselves, report flight plans, and inform ground control of their exact position. Such regulations apply to commercial aircraft as well as military aircraft. On the latter count, China’s ADIZ fails to uphold the normative principle that military aircraft simply transiting through an ADIZ shouldn’t be obliged to report to the host country. China has threatened to meet non-compliance with “military defensive measures.” The U.S. State Department was highly critical of the coercive measure, claiming that “the U.S. does not apply its ADIZ procedures to foreign aircraft not intending to enter the U.S. national airspace.” The State Department urged China “not to implement its threat to take actions against aircraft that do not identify themselves or obey orders from Beijing.”
China’s reinterpretation of how an ADIZ is declared and operates raises questions about the legality, legitimacy and intentions of its controversial efforts over the ECS. ADIZs are legally ambiguous, and aren’t regulated by any defined international regime. Although there’s no explicit prohibition on ADIZs, they can be used in ways that violate other international legal provisions. China’s specific identification requirements placed on military aircraft are in violation of Article 87 of the United Nations Convention of the Law of the Sea (UNCLOS), which protects “freedom of overflight” and to which China is a signatory. The 1944 Convention on International Civil Aviation – the Chicago Convention – also rules against unilateral attempts to restrict air navigation beyond a state’s territorial seas. Therein lies the danger: China’s attempt to maintain de-facto control of its surrounding waters will contribute to establishing a precedent outside of current international law.
Worryingly, China has recently signaled its willingness to treat its ADIZ as an extension of its sovereign territory. According to Air Transport World, a Laos Airlines plane flying through China’s ADIZ in late July was requested to fly back as it hadn’t met its reporting requirements. Despite vehement denials from China’s Ministry of National Defense that the “event has no connection with the ADIZ in the East China Sea” and silence from the Laotian government, presumably due to fear associated with upsetting Sino-Laos trade relations, the incident is potentially a sign of things to come. Moreover, the possibility that China may declare an ADIZ over the South China Sea only brings more uncertainty to the protection of freedom of overflight in international waters.
So what can be done to mitigate the chances of escalation in the ECS and the possibility that China will announce an ADIZ over the SCS?
Despite tough rhetoric emanating from the U.S. immediately after the declaration of the ADIZ over the ECS and later dispatch of two American B-52 bombers to fly through the zone, the U.S. response has been relatively quiet overall. Although U.S. President Barack Obama employed tough rhetoric when pledging that Article V of U.S.–Japan Treaty of Mutual Cooperation and Security provided an “ironclad” security guarantee to protect the Senkaku/Daioyu islands in the ECS, a lack of tangible U.S. action has hardened China’s claims of sovereignty over the disputed waters. It’s imperative that the U.S. continues to fully exercise its right to fly its military aircraft through the East China Sea.
As a regional power in the Indo–Pacific region, Australia also has a role in upholding freedom of overflight in its neighborhood. The initial condemnation of China’s ECS effort by Australia’s Foreign Minister Julie Bishop must be bolstered with action so as to avoid Chinese de-facto control over the ECS. It’s important that Australia unilaterally flies its military aircraft through the ECS ADIZ, or publicly demonstrates support for allies who do so to avoid the emergence of a new status quo where China rules its surrounding seas. Inaction has the potential to encourage China to declare a South China Sea ADIZ in the foreseeable future.
Now that Xi Jinping’s visit to Washington is out of the way, China might see a window of opportunity to declare an ADIZ in the SCS before the International Court of Arbitration rules on the Philippines’ territorial claim in the near future. Australia must act sooner, rather than later, to protect its right of overflight or it may one day face a situation where it requires permission from China to exercise its own international freedoms.
Alice Slevison is a Research Intern at the Australian Strategic Policy Institute in Canberra, Australia. This article was previously published in ASPI Strategist.