HONOLULU -- There's every reason to celebrate as the United States and Japan commemorate 150 years of diplomatic relations this year. The bilateral relationship is the best ever, surpassing even the Golden Age of the "Ron-Yasu" years (1982-87). Credit a decade of preparation, hardworking bureaucracies in both governments, a savvy prime minister, and a U.S. administration that looks to Japan to play a major role in Asia.

Yet, amid the congratulations, it's hard to escape the feeling that there is considerably more enthusiasm in Washington than in Tokyo. Officials and observers in both capitals say the relationship has hit new heights, but among Japanese there is more skepticism and more concern that this high tide may recede -- sooner than many anticipate. The task for both governments is to seize the moment and create a structure that institutionalizes a new U.S.-Japan relationship.

Japanese supporters of the alliance worry about Tokyo's dispatch of Ground Self-Defense Force units to Iraq. Japan's historic deployment is laden with risk; casualties are a very real possibility. Few believe, however, that fatalities would force Tokyo to withdraw the troops. Prime Minister Koizumi Junichiro and other members of his government understand that such a move would only embolden terrorists.