On Tuesday, the Japan Defense Agency becomes the Japan Ministry of Defense in a change that seems small on the surface, but is substantial in its underlying reality.

In Japanese, the new name requires changing only one ideograph, from "cho" to "sho." In Romanized Japanese, it is but one letter. And in American English, most people would not see much difference between "agency" and "ministry."

In a nation often driven by symbols, however, this shift reflects a newly assertive Japan that some Japanese say seeks to be a "normal" country. Moreover, it responds to a perceived threat from North Korea and reflects Japanese anxiety over potential threats from China.

The Diet, Japan's legislature, authorized the revision last month with surprising little opposition, given the pacifist stance of left-wing parties in the past. The new prime minister, Shinzo Abe, asserted to the press that the transition to the Ministry of Defense "demonstrates both domestically and internationally the maturity of Japanese democracy."

He contended the change showed "our confidence in civilian control. It also sends a signal that Japan is prepared to contribute even more to the international community, and that it will take on its role responsibly."

In practical politics, the director general of the Defense Agency becomes the minister of defense and a member of the Cabinet that presides over the executive branch of Tokyo's government. That Cabinet of a dozen ministers drawn from the Diet is roughly the equivalent of the U.S. presidency, a fact often overlooked outside of Japan.

Until now, the head of the defense agency was something of a political nonentity. Sometime in the past, the only thing one director general of the agency was able to accomplish was to have a military band parade in his hometown.

On becoming a full-fledged member of the Cabinet, the defense minister will have more say about his ministry's budget than in the past, when it was fashioned largely by bureaucrats from the prime minister's office and the Finance Ministry. For decades, however, Japan has limited its military spending to 1 percent of gross national product and that seems unlikely to change any time soon.

Internationally, in dealing with the U.S. secretary of defense or top defense officials of other nations, the Japanese defense minister will be treated now "as an equal governmental chief in both name and reality," says Tokyo's 2006 white paper on defense. In prestige-conscious Japan, this counts.

Japan's Self-Defense Forces, however, will keep their names, both in Japanese and in translation. The Japan Ground Self-Defense Force will not become the Japanese army and the Japan Maritime Self-Defense Force will not become the Japanese navy. At least not yet; some senior retired officers have been quietly lobbying for those names to be revised, too.

The birth of Japan's Defense Ministry is part of a plan to improve Japan's security. Prime Minister Abe says he wants to amend Article IX of the constitution, under which Japan has renounced force as an instrument of national power. It has been at the heart of Japanese pacifism for 60 years; a revision would constitutionally permit Japan to use military force to protect its interests.

The prime minister also has said Japan needs a national security council patterned on that in Washington and should form an agency to gather and analyze intelligence. Today, the Japanese prime minister has only a small research office to provide analyses of events and trends abroad.

The North Koreans and Chinese have criticized the elevation of the defense ministry. The (North) Korean Central News Agency, controlled by the government in Pyongyang, said that turning the defense agency into a ministry was intended to realize Japan's "militarist ambition for overseas expansion."

Similarly, an official Chinese newspaper, the People's Daily, contended that the shift reflected "a change in nature" for Japan's defense establishment as it "clears barriers for the Japanese armed forces on their way of going beyond self-defense."

What the North Koreans and Chinese fail to realize is that their belligerence toward Japan has accelerated a Japanese revision in their thinking on military power and caused Tokyo to strengthen its defense ties with the U.S. as the Americans realign their forces in Asia.

In the normal course of events, Japan would most likely have gradually shed its postwar pacifism in favor of a more assertive posture. The North Koreans and Chinese, however, have brought that day forward, which would not seem to be in their own best interests.

Richard Halloran is a Honolulu-based journalist and former New York Times correspondent in Asia. His column appears weekly in Sunday's Focus section.