Meanwhile, China Draws a Provocative, Dangerous, But Perfectly Legal Air Defense Identification Zone in the East China Sea

Meanwhile, China Draws a Provocative, Dangerous, But Perfectly Legal Air Defense Identification Zone in the East China Sea

£¨Í¼±í£©[¶«º£·À¿Õʶ±ðÇø]¶«º£·À¿Õʶ±ðÇø»®ÉèʾÒâͼI don’t have any insights to offer on the big news this weekend, that legally-non binding-UNSC-resolution-violating agreement in Geneva.  But I did want to note one other big sort-of-law news item from the other side of the world: China’s announcement that it is drawing an Air Defense Identification Zone (ADIZ) in the East China Sea, including over the disputed Diaoyu/Senkaku Islands.

China’s announcement has riled up both Japan (which has declared it “totally unacceptable”) and the United States (which has expressed “deep concerns.”)

Why all the fuss? China’s new ADIZ appears to overlap with Japan’s own ADIZ in some crucial places (like the Senkakus/Diaoyu) as well as South Korea’s and Taiwan’s.  China has declared that aircraft entering its ADIZ must report flight information to Chinese authorities (actually, its military) and (here’s the scary part), “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.”  The U.S. is already hinting that it will test this resolve by flying aircraft through the ADIZ.  (Wonder which lucky US pilot draws that mission!)

Although provocative and dangerous, it seem clear to me that China’s ADIZ does not violate international law.  Indeed, China’s Foreign Ministry was perfectly correct today in its claim that its ADIZ is consistent with “the U.N. Charter and related state practice.”  Countries (led by the U.S.) have long drawn ADIZs beyond their national sovereign airspace as a measure to protect their national airspace.  This practice, although not exactly blessed by any treaty, does not appear to violate either the Chicago Convention or UNCLOS.  (See Peter Dutton’s very solid review of ADIZs here in the American Journal of International Law for a good discussion on this point).

If China has sovereignty over the Diaoyu Islands, then it is perfectly legal for it to declare an ADIZ beyond those islands to protect the airspace above those islands.  It is a little less clear why China needs the rest of the ADIZ, but it is presumably aimed at protecting its national airspace.  The U.S. State Department has already offered China an interpretive out of creating unnecessary conflict:

The United States does not apply its ADIZ procedures to foreign aircraft not intending to enter U.S. national airspace. We urge China not to implement its threat to take action against aircraft that do not identify themselves or obey orders from Beijing.

Now the accuracy of this description of US practice could be questioned, but it is probably right. In recent years, the U.S. has allowed Russian bombers to fly through its ADIZ over Alaska.  If China follows this practice, this could help a great deal to diffuse tensions. One can only hope. Early signs are not promising,as China has essentially told the U.S. to shut up and butt out of this issue.

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Asia-Pacific, General, Law of the Sea
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Ryan Scoville

“If China has sovereignty over the Diaoyu Islands, then it is perfectly legal for it to declare an ADIZ beyond those islands to protect the airspace above those islands.” 
That seems like a gigantic and intractable “if.” The ADIZ is perfectly legal only if you assume away the central issue.

Craig H. Allen

Response…is anyone aware of another ADIZ around unoccupied islets?

Ian Henderson
Ian Henderson

I think there are two different issues at play. The first, the declaration of an ADIZ. The second, the ‘rules’ associated with that ADIZ.
Based on State practice, it is pretty clear that a State can declare an ADIZ in appropriate circumstances. However, as the rationale for an ADIZ is to protect national security, there is arguably a difference between declaring an ADIZ adjacent to the mainland or an occupied island, and declaring one adjacent to a mere rock. Of course, an ADIZ adjacent to the mainland that extends for over 100 or more nautical miles might also cover unoccupied rocks. However, such an ADIZ could not overlap another State’s national airspace — athough it could overlap another State’s ADIZ.
Even though the declaration of a particular ADIZ might be lawful, the second issue is the rules associated with the ADIZ. Perhpas the most important issue is that an ADIZ cannot affect freedom of navigation in international airspace. For example, it cannot impose operating restrictions on state aircraft beyond flying with due regard.


Ryan has a very good point.  And, in context (which must involve adequate attention to Article 33 of the U.N. Charter), has the PRC stepped over a line from a making viable defensive claim to create an ADIZ to a threat of force in violation of Article 2(4) of the United Nations Charter?  Is this a “back-door” threat to use armed force in violation of Article 33 of the Charter?


CNN reports that the U.S. flew two unarmed B-52 bombers into the claimed ADIZ without identifying themselves to the PRC.
This is generally called “interruption” of a claim — as in the case of U.S. naval vessel interruptions of Qadafi’s claimed “line of death” bay-closing line that was violative of the customary law of the sea.

Mark E. Rosen
Mark E. Rosen

ADIZs are supposed to be linked to a country’s right to defend itself against unannounced aircraft and is related to a coastal state’s right to condition access into it’s airspace.   The US has a large ADIZ established in the Code of Federal Regulations which is explicitly related to protection of the “contiguous united states.”  
This zone is highly problematic as a matter of international law because the purpose is related to China’s efforts to demonstrate occupation of the disputed islands.   That’s what their embassy has essentially said.   So on that level, there’s a problem.     
The second problem is that the zone will ensnares lots of North-South civil aviation that it totally unconnected with the dispute and not destined for the PRC.   I’m guessing that is the reason that the US went to extraordinary lengths to send a B52 to conduct a Freedom of Navigation challenge.   That type of action hasn’t been done since the US challenged Libya’s closure line on the Gulf of Sidra.   
This is a very disturbing development given China’s other excessive maritime claims; including its notorious 9 dashed line claim.   

Itzchak Kornfeld
Itzchak Kornfeld

I disagree with Julian’s point that China’s current actions are legal under international law.
In the ADIZ, the dispute over the Diaoyu/Senkaku islands and other issues related to territory China has sought to invoke what it claims is its “sovereignty”. However, I believe that these claims are spurious at best, at least at this point in time.  As other commentators have noted an ADIZ is zone of protection of a coastal state’s territory.  But China is not taking such a position.  It does not need to “protect” itself from hostile powers.
I am reminded of this year’s ASIL meeting where a speaker from China and a government official also from China demanded that China has a right to exercise its sovereignty.  I was struck by their tone: like a little child jumping up and down to make it point.
But, one point that has not been raised here is that Japan long-ago declared its sovereignty over the islands.  It is also a change in the status quo, which includes territorial disputes with the Philippines.
If China truly believes that its territorial claims are legitimate, it should these claims to the ICJ, rather than rattling its sabers.


Itzchak’s suggestion of dispute resolution before the ICJ would allow all to save face and avoid a serious incident — and to avoid further threats of armed force that can violate Articles 2(4) and 33 of the Charter.

Michael Turton

China has no sovereignty over the Senkakus; the claim is a post-1971 invention that has no legal or historical basis. I touch on that briefly at The Diplomat.

The Senkaku claim is pure territorial expansion. Hence the ADIZ is probably illegal, in addition to being belligerent. It should be read as a kind of signal, like the Panay sinking or the remilitarization of the Rhineland or the Spanish attack on Hawkins and Drake off San Juan de Ulua, of where events are headed. 

Michael Turton The View from Taiwan