If Japan's immediate protest against China for establishing the Air Defense Identification Zone over the East China Sea in late November was a knee-jerk reaction, its approach over the past three weeks (and likely moves in the days ahead) has been one of playing up the China "threat" theory. Japan's moves, needless to say, are a prelude to its diplomacy toward China in 2014.

Not surprisingly, China, although uninvited, topped Japan's agenda of the Dec 13-15 special summit between Japan and the Association of Southeast Asian Nations in Tokyo. However, the joint statement without mentioning China's ADIZ indicated Japan's "China threat" card didn't play well.

The Japanese cabinet could endorse a draft of its first national security strategy as early as this week, confirming Tokyo's commitment to building a stronger military to counter perceived security threats from China. When the near-final draft was released last week, Japanese Prime Minister Shinzo Abe termed it "historic", saying it would form the basis of Japan's defense policies to be devised by the newly established National Security Council.

Conservative hawks have, as expected, defended the controversial state secrecy bill - railroaded through the Diet recently against overwhelming public opposition - claiming it is vital for making the US-style body negotiate with Japan's allies over possible sharing of intelligence.

These moves reflect the rightist tilt in the Japan's foreign and defense policies, which are steps toward strengthening the country's military using the China "threat" theory and China's ADIZ as pretexts. But Japan should know that China's ADIZ cannot be used as a pretext for its military buildup. As a sovereign state, China has done nothing illegal; it has not violated the Charter of the United Nations or any other international law in following a globally acceptable practice.

The United States and Canada took the lead in setting up ADIZs in the 1950s. Today, more than 20 countries and regions, including Japan, have ADIZs in place, although their regulations vary. For instance, Washington claims that it does not apply ADIZ procedures to foreign aircraft not intending to enter US airspace, but Ottawa does even if foreign aircraft have no intention of entering Canadian airspace.

Despite the lack of unified ADIZ regulations, ADIZs have been set up by many countries to defend national security, and China's ADIZ is no different. The fierce reaction of Japan, therefore, reveals a certain degree of ignorance, if not a deliberate attempt to distort the nature of China's ADIZ. That the freedom of over-flight in the region remains unaltered even after the establishment of China's ADIZ refutes Japan's alarmist talks.

In urging Beijing to withdraw its ADIZ and spreading baseless alarm, Tokyo is conveniently ignoring the fact that it is the one that altered the status quo last year by "nationalizing" parts of the Diaoyu Islands.