Since last Saturday, when China declared an "Air Defense Identification Zone" (ADIZ) that covers the disputed islands called Senkaku in Japanese and Diaoyu in Chinese, the media have been full of predictions of confrontation and crisis. On that same day Japan scrambled two F-15 fighters to intercept two Chinese aircraft that approached the islands.
"This announcement by the People's Republic of China will not in any way change how the United States conducts military operations in the region," said U.S. Defense Secretary Chuck Hagel. And on Tuesday the U.S. Air Force flew two B-52 bombers from Guam into the ADIZ. A Pentagon spokesman said Washington "continued to follow our normal procedures, which include not filing flight plans, not radioing ahead and not registering our frequencies."
But forcing incoming aircraft to do just that is the whole point of creating an ADIZ. Aircraft entering the zone must provide a flight plan, maintain two-way radio communications and clearly identify their nationality, said the Chinese Defense Ministry, and aircraft that ignore the rules would be subject to "defensive emergency measures."