Sunday, on the 59th anniversary of the end of World War II, four Japanese government ministers visited Tokyo's Yasukuni Shrine. This Shinto site honors the nation's nearly 2.5 million war dead, but many of them are considered war criminals, including 14 people judged as "Class-A" war criminals.
Last week, Prime Minister Junichiro Koizumi said he would visit this symbol of his nation's past militarism next year, as he has done four times since taking office. As expected, China, which was brutally occupied by Imperial Japan, expressed outrage.
This diplomatic dust-up is just another sign of cooling ties between Asia's two economic giants.
The bilateral estrangement of China and Japan is not a trend that the US, Europe, and especially other Asian nations should underestimate.
China's eventual economic and political challenge to the world as a potential superpower is being played out now in its rough treatment of Japan. The underlying tensions between the two peoples erupted earlier this month in China during an Asian Cup soccer match that Japan won. Chinese fans heckled the Japanese players, cowed Japanese fans with historical insults, and forced officials to deploy some 6,000 police.
The two nations also recently sparred over several islands in the East China Sea that they both claim. And China was incensed last year when hundreds of Japanese "sex tourists" were caught with Chinese prostitutes. Beijing is also alarmed at Japan's steady drift to revive its military and Japan's adopting a US-made missile defense shield.
After years of trying to befriend China with huge loans, Japan has begun to realize that Beijing finds it useful to unify the Chinese behind the Communist Party by occasionally letting loose nationalist and historical resentments against Japan. That tactic also helps China win over other Asian nations in new alliances, sometimes at Japan's expense.
China, meanwhile, suspects that Japanese leaders are using the Chinese "threat" to rally domestic support in favor of ending Japanese pacifism.
Despite their booming $160 billion in trade, Japanese and Chinese leaders haven't done much to smooth relations. The usual exchange of leaders from years past hasn't taken place under Mr. Koizumi.
But just as Germany and France reconciled after World War II, eventually Japan and China will need to form a stable alliance.
Japan and South Korea set aside their bitter past in recent years to become closer, even cohosting the last World Cup. Beijing and Tokyo must soon get over their deep suspicions and create a stable and peaceful environment for Asia.