China’s move to implement an Air Defence Identification Zone in the East China Sea has sparked concern among its eastern neighbours and the United States. That the ADIZ so marked includes the Senkaku/Diaoyu islands — whose ownership is contested by China and Japan — has riled Japan and the U.S., prompting Washington to send B-52 bombers over the Zone. China admittedly is well within its rights to demarcate such an ADIZ. Air defence identification zones serve as buffer airspace for countries, extending in some cases beyond territorial waters. It is the prerogative of littoral states to determine how they should respond to civilian or military aircraft entering an ADIZ. The U.S. and Canada have identified air defence zones that cover hundreds of miles beyond their territorial seas — the U.S., however, maintains that only military aircraft are required to inform the authorities while crossing this space and that too if they intend to fly towards the mainland. India has marked six such zones hugging its coastline, with stringent clearance requirements for all aircraft entering them. Whether China has unilaterally implemented an ADIZ is inconsequential and it is conceivable that air defence zones of neighbouring countries may overlap. Japan, for instance, identified an ADIZ bordering Taiwan earlier this year without consulting Taipei, stoking a controversy.
The question, then, is not one of legality but propriety. Some directives contained in China’s ADIZ announcement were rather alarming. China’s announcement that its “armed forces would adopt defensive emergency measures” — presumably going well beyond identification or interception — against non-cooperating aircraft, was problematic especially in the light of a standing dispute over some territories in the Zone. The Chinese government may have intended to remind the U.S. that it is the dominant power in the region. Yet ironically, this episode has brought the U.S. and its allies together in a huddle. Beijing must also now contend with its increasingly vocal nationalist constituency that has been demanding “countermeasures” against violating aircraft. The U.S. too must desist from creating further friction in the region. After an initial display of bravado in sending bomber planes over the ADIZ, the U.S. has asked its commercial aircraft to “operate consistent with notices to airmen issued by foreign countries.” China should now respond in kind and assuage the legitimate concerns of its Asian neighbours. The Chinese Defence Ministry’s clarification that the “Zone does not aim at any specific country or target, nor does it constitute a threat to any country or region,” is a welcome measure.