01:00 AM EDT on Thursday, July 20, 2006

SAN FRANCISCO

FROM APPEARANCES, the recent summit between President Bush and Japanese Prime Minister Junichiro Koizumi was a tremendous success. It certainly seemed that way as Koizumi, an Elvis fan, beamed from behind his gold-rimmed sunglasses during a visit to Graceland with the president. But behind the smiles, the U.S.-Japanese relationship is undergoing strain. This strain may ultimately work to the benefit of both countries, but only if it is managed correctly.

The post-war Japanese constitution expressly renounces war as a sovereign right of the state. This, however, has not stopped Japan from developing its Self-Defense Forces (SDF) into one of the most capable militaries in East Asia. During the Cold War, the SDF served U.S. interests well, as Japan provided a bulwark against communist expansion in the region. Today, as the exaggerated concept of "China as enemy" becomes more accepted, Japan's military prowess continues to serve U.S. interests.

But Japan is becoming more essential to U.S. interests in less codified ways. Under the U.S.-Japan Mutual Security Treaty, the United States maintains an array of military bases in Japan that can be used in the defense of Japan proper or to maintain "peace and stability" in East Asia. But a recent report by the Nautilus Institute found that U.S. AEGIS destroyers based at Yokosuka were maintaining semi-regular patrols in the Sea of Japan that bestrode potential missile flight paths from North Korea to the United States.

In other words, U.S. military assets based in Japan were taking part in U.S. homeland-defense operations. This activity could be interpreted as running afoul of both the U.S.-Japanese treaty and Japan's pacifist constitution.

Conversely, the U.S.-Japanese relationship can be interpreted as becoming less essential but better codified. This year, the two countries agreed on a comprehensive realignment of U.S. military forces in Japan. Some U.S. bases in Okinawa will be closed and consolidated, and the military will relocate several thousand personnel from Japan to Guam.

Although Japan will remain home to significant numbers of U.S. troops, the agreement represented an explicit mutual understanding that the U.S. military presence in Japan would be reduced.

These two countervailing tendencies in the U.S.-Japanese alliance -- its becoming more essential but less codified, and vice versa -- highlight the need for a more mature relationship. Under Prime Minister Koizumi, Japan has inched closer to constitutional revisions that would make it easier for the Self-Defense Forces to participate in peacekeeping and support operations abroad.

Such potential revisions have met with opposition both in Japan and among its neighbors, which never hesitate to remind the world of Japan's atrocities during World War II. It is certainly true that Japan has not adequately reconciled its collective memory with its wartime actions, and Koizumi's visits to the controversial Yasukuni shrine only aggravate serious regional tensions. But it is also true that when China, Korea and others hold Japan hostage to its history, they perpetuate a circular argument incapable of generating diplomatic progress.

A Japan that is a fully capable member of the global community will benefit both the United States and East Asia.

From the perspective of the United States, more transparency is required in its relationship with Japan. Most important, the Bush administration would be well advised to avoid further vilification of China. While that country may one day represent a genuine security threat, an exaggeration of that threat for domestic political purposes only aggravates the tense and long-competitive China-Japan relationship.

Fundamentally, the United States and Japan remain strong allies. Koizumi supported the U.S. interventions in Afghanistan and Iraq, and provided Self-Defense Forces in each theater. And last year Japan and the United States agreed to designate China-Taiwan tensions a "mutual security concern."

Amid the recent North Korean missile tests, the United States has accelerated plans to install Patriot anti-missile batteries in Japan and publicized the routine deployment of another AEGIS destroyer to the region. And, Elvis theatrics aside, the successful Koizumi-Bush summit exemplifies the close relationship between the leaders of the two countries.

Clearly, the U.S.-Japanese relationship will continue to form the bedrock of East Asian security for some time to come. But unless the tensions inherent in the relationship are relieved in smart, pragmatic ways, the alliance will become increasingly overburdened and ineffective.

Daniel Widome, an occasional contributor, is a San Francisco-based writer and foreign-policy analyst (Daniel.Widome@gmail.com).