Three thoughts as regards the Chinese declaration of an Air Defense Identification Zone (ADIZ) including the airspace over the Senkakus.
1) Some of the world's media and Japanese officials have portrayed the U.S. Air Forces' flying of two B-52s unannounced into the Chinese ADIZ on November 26 as a gutsy finger-in-the-eye response to the Chinese declaration. Some in Japan also see it as a strong vote in support of the Japanese government's contention that the zone is invalid. (Link)
This would seem to be an over reading of the U.S. Defense Department's actions.
U.S. military aircraft never announce their entry into the ADIZs of other nations, unless of course under orders to do so. Not alerting the Chinese as to the entry of the B-52s into the new ADIZ was standard operating procedure.
So the B-52s were not challenging Chinese resolve. They were just flying.
2) Some commentators on last week's events concluded that while there may be teething problems and that some adjustments may needed, China's new ADIZ is entirely within its rights and is thus here to stay. (Link)
ADIZs are seen as extensions of a country's right to establish conditions for entry into its territory or airspace. An ADIZ thus assumes a clear position on sovereignty.
By declaring an ADIZ extending over the Senkakus, over which Japan has had administrative control since 1972 and which the Japanese government insists are Japan's alone, the Chinese government has taken the argument over its claims on the Senkakus out of the realm of conjecture and the hands of Coast Guard ship commanders and given it over to military air forces commanders and fighter pilots on both sides -- with all the possibilities of errors snowballing into mass conflict that such a handover might produce.
If China were to now try to ease tensions by carving out from their new ADIZ the airspace above the Senkakus and the corridor projecting back to Japan's airspace, the resulting ADIZ would not affect the status quo in terms angry meetings of militaries. It would, however, be read as a tacit acknowledgement of Japan's sovereignty over the Senkakus.
So the ADIZ will either result in the degradation of Chinese security or the undermining of China's territorial claims on the Senkakus.
So China is within its rights? Maybe. Within its right mind? Seemingly not.
3) By declaring that it will enforce its claims over the Senkakus with fighter jets, the Chinese have brought the tale of the Senkakus close to its only reasonable end game scenario, undoing the damage inflicted upon the region by the duplicitous, self-serving Nixon Administration: the United States recognizing Japanese sovereignty over the islands.
One hopes that Vice President Biden made this point clear in his talks with President Xi two days ago.