Seiji Ozawa won't raise his baton in Beijing this week, flooding the Great Hall of the People with the glorious sound of Beethoven's Leonore Overture as Jiang Zemin and Zhu Rongji listen attentively. Instead, two Boston Symphony Orchestra performances have been cancelled in the escalating diplomatic row between China and the United States over the Belgrade bombing of the Chinese embassy. The concerts were supposed to mark the 20th anniversary of similar ones attended by the late Deng Xiaoping as a symbol of warming ties between the two nations. This week's non-performances symbolise the exact opposite. The cancellation is a blow to Chinese music-lovers but one which can be endured. But, more importantly, it is accompanied by the postponement of official Sino-American exchanges on human rights, military strategy, arms control and nuclear proliferation - all key to an effort to deepen relations. This raises questions of more fundamental concern to the region and the world: To what extent is China ready to weaken its US ties and for what purpose? The fatal attack on the Chinese embassy was a tragic mistake which hasn't yet received adequate explanation; merely calling it an intelligence error isn't enough. But the raid was so self-damaging to Nato's political cause that it is impossible to believe it happened on purpose. Yet the official China Daily, among others, chooses to call the bombing an 'intolerable aggression and a war crime' against China which betrays an 'ambition to dictate world politics'. In fact, the bombing was more stupid than conspiratorial, and Nato leaders have been offering abject apologies publicly and privately ever since it happened. However, none of these expressions of regret, nor a declared willingness to pay reparations, have been relayed to the Chinese public by the state-controlled media. Instead, Beijing organised rowdy protests for reasons which go far beyond the understandable wish to vent anger over an inexcusable loss of innocent life. These apparently include a desire to warn against getting dangerously close to foreign powers. However, yesterday's demonstrations were smaller and less violent, and there were indications they will soon end as 'spontaneously' as they began. But other questions linger. Will this episode be exploited by conservative leaders who oppose exposing China to competitive economic pressures, notably by joining the World Trade Organisation? Will it erode the authority of Premier Zhu and his fellow reformers? Do the cancelled talks with US officials symbolise a pause or a more basic freeze for internal Chinese reasons? These longer-term questions cannot yet be answered. But they point to a crucial problem: by unleashing such furies, China may have turned loose forces which can bring consequences contrary to its own national interests and those of the entire region.