SINGAPORE -- U.S. Secretary of State Colin Powell's recent visits to Japan, South Korea and China were a key test of U.S. diplomacy in Northeast Asia. His renewed focus on the region comes amid growing anxiety in Tokyo and Seoul over Pyongyang's nuclear brinkmanship and increasing resistance on the part of Moscow and Beijing to the hard line the United States has adopted toward both Iraq and North Korea.

Washington's traditional alliances and ties are being challenged in Northeast Asia as China's influence increases. Russian influence in the region is growing as well. Japan's decline, meanwhile, contrasts starkly with the rise of the Chinese giant. Already in dire straits, the weak Japanese economy will suffer substantially more if the Korean crisis causes regional confidence to further erode.

Tokyo has urgently looked to Washington for security assurances, even though the U.S. military presence in Japan continues to stir controversy (although to a lesser degree recently because of Pyongyang's actions). The Japanese government is now walking a diplomatic and political tightrope between openly siding with Washington on Iraq and Pyongyang, and keeping the door open to negotiations with Pyongyang in line with the diplomatic wishes of Seoul, Beijing and Moscow.