I don't wish to become entangled in debate over whether other states impose such ADIZ identification zones beyond their territorial waters, as asserted by Beijing. It is political infantilism to see and judge such disputes through a moral prism, as if our Hobbesian world conforms to codes of right and wrong. What we are dealing with is a great power collision of epochal proportions.
The Asian arms race is young, but clearly under way already. China has launched its first stealth drone, known as Sharp Sword. It developing indigenous aircraft carriers. Its “Two-Ocean-Strategy” implies a fleet of five or six carrier battle groups.
Japan is already rearming. It is building a de facto marine force. It has launched its largest warship since WW2, an 800-foot long DDH-class helicopter carrier, an aircraft carrier in all but name. Tokyo is developing its own version of the Pentagon's Advanced Research Projects Agency. Spending on warships and aircraft will jump by 23pc this year.
When I visited the spanking new buildings of the Japanese defence ministry in Tokyo in March, it already seemed like another world from the run-down digs of the old Self-Defence Force that I had visited six years earlier.
You could feel the emergence of a new military power, pacifist still in name only. The message that came through loud and clear from talking to officials is that Japan is ready for a fight if necessary, and is convinced that it can sink or shoot down any force sent by China into Japan's waters and airspace – whether to close in on the Senkaku/Diaoyu islands, or to ratchet up pressure against Okinawa.
I was shown detailed maps tracing movements of Chinese DDG warships and Yuan-class submarines that left me deeply alarmed over where this is going. Japanese officials said Chinese naval officers on patrol were not responding to normal signals.
"What we don't know is whether Chinese officers follow any international code of conduct? Do they understand what is banned and not banned? Does the Communist Party control their own military?" said one defence planner.
"Two thousand years ago under the Han Dynasty, the emperor put his right hand on the wheel of his chariot and told his general that everything inside the borders was the domain of the emperor, and everything outside was left to the commander. That has plagued China throughout its history, and it is the delicate issue we now face," he said.
There is no red telephone between Tokyo and Beijing to defuse a crisis if it erupts, nothing comparable to the Washington-Moscow "hotline" during the Cold War.
While the US and China were able to calm the waters after an American military jet collided with a Chinese fighter in 2002 – killing the Chinese pilot – it is unlikely that any such mishap between China and Japan could be contained at this stage.