What’s the Deal with China’s New Air Defense Identification Zone?


Early on Saturday, the People’s Republic of China announced the establishment of an Air Defense Identification Zone over much of the East China Sea and has already conducted its first air patrol of the zone with two large.  Early warning aircraft and fighters provided support and cover.

What does this mean?

According to a spokesman for the PLA, the zone “is an area of air space established by a coastal state beyond its territorial airspace to timely identify, monitor, control and react to aircraft entering this zone with potential air threats. It allows early-warning time and provides air security.” It has issued a set of rules for aircraft to follow, including identification of themselves and their flight path.  Ominously, the PRC states, “China’s armed forces will adopt defensive emergency measures to respond to aircraft that do not cooperate in the identification or refuse to follow the instructions.”

China claims the zone “is not directed against any specific country or target,” but this is clearly not the case.  The zone covers territory claimed by both Japan and China – the Senkaku Islands – and there have been a series of incidents and disputes related to this territory.  China claims to be “following international practice” but it is not clear what practice they are referring to. They claim it is “a necessary measure taken by China in exercising its self-defense right. It is not directed against any specific country or target. It does not affect the freedom of over-flight in the related airspace.”

Where is the zone? 

According to China, the zone “includes the airspace within the area enclosed by China’s outer limit of the territorial sea and the following six points: 33º11’N (North Latitude) and 121º47’E (East Longitude), 33º11’N and 125º00’E, 31º00’N and 128º20’E, 25º38’N and 125º00’E, 24º45’N and 123º00’E, 26º44’N and 120º58’E.”  China’s Defense Ministry has released this map.

China Air Defense Zone

Is there precedence for this?

China thinks so. They state:

Since the 1950s, more than 20 countries including some major countries and China’s neighboring countries have successively established Air Defense Identification Zones. Chinese government’s relevant behavior is in line with the UN Charter and other international laws and customs. China’s domestic laws and regulations such as the Law of the PRC on National Defense, the Law of PRC on Civil Aviation and Basic Rules on Flight have also clearly stipulated on the maintenance of territorial land and air security and flight order.

The United States and Canada have their own Air Defense Identification Zone (map here).  A more relevant example might be Japan’s own Air Defense Identification Zone, which looks as if it overlaps with China’s, although I’m unable to locate a reliable map of it.

Key Questions (none of which I know the answer to): 

  1. Is China acting within international norms?
  2. How will the United States and Japan react?
  3. How will other states involved in territorial disputes with China react? Will they rally around Japan?  South Korea’s response, in particular, will be interesting as they are involved in their own acrimonious territorial dispute with Japan.
  4. Will the United States finally get serious about the “re-balance” to Asia?
  5. Is China just seeing how far it can go?
  6. If the Japanese and Chinese zones overlap, doesn’t this increase the likelihood of an ugly confrontation?

I’m very interested in hearing from our readers in the comments section as the crisis develops. I’m sure we’ll be hearing from WOTR’s military and Asia specialists as this progresses.


Ryan Evans is the assistant director of the Center for the National Interest and the editor-in-chief of War on the Rocks.