The relationship between Washington, Beijing and Taipei may be the weirdest in the world. Here is why. The Bush administration is getting manoeuvred into a kind of China box, and there may be no easy exit. Perhaps the risk of this emerging dynamic is less obvious these days as the humanitarian efforts of the US, its friends and allies in the tsunami recovery in Asia understandably occupy centre stage. But underneath are newly churning waters of the triangular relationship that could prove to be of tsunami strength in its destructiveness.

From Beijing comes new evidence of determination to keep Taiwan from slipping away any further. Mainland China's leaders regard the integration of the island as the highest non-economic policy priority.

Last month, the National People's Congress declaimed that it would be necessary to mint a new anti-succession law to lay down an unmistakable line in the sand for obstreperous Taiwan.

Last week, Chen Yunlin , head of the mainland's Taiwan Affairs Office, conferred with a top US State Department official in Washington about the nature and intent of the new legislation. This unusual high-level meeting - aimed at securing at least Bush administration neutrality, if not support, for the proposal - came at about the same time that Beijing was sending another slap Taiwan's way: the mayor of Taipei, Ma Ying-jeou, was denied a visa to visit Hong Kong.

This was curious. Mr Ma is a veteran politician and member of the Kuomintang, which does not favour formal Taiwan independence. Perhaps the best interpretation is simply to imagine Beijing in deadly fear that a high-level visit by the charismatic Mr Ma to Hong Kong might trigger widespread discussion of the ever-hotter Taiwan situation. Who really knows?

And so there is evidence of a tightening of the pressure around Taiwan. And the timing is not coincidental. The Bush administration needs to figure out some way to get out of the Iraq quagmire without losing face; to do that, it needs to avoid major military conflict elsewhere. This is where Beijing's sense of timing comes in.

For the foreseeable future, America requires a decent relationship with Beijing as much as Beijing wants good ties with the US. This is especially the case with the North Korean problem, where Beijing has taken the lead in organising the six-party talks that involve, besides Washington, Tokyo, Seoul, Moscow and Pyongyang. The talks are not going well, but the framework remains intact.

At a recent foreign-policy lunch in Washington for members of the establishment, former national security adviser Brent Scowcroft said it would be all but a disaster if the talks did break down; but it would be an unmitigated disaster for the Sino-US relationship if Washington was seen to be the deal-breaker. The US must not be held to blame, said Mr Scowcroft: "If there's a breakdown, China must stay on our side." And he meant more or less across Asia in general.

Stress on the Sino-US relationship is now the last thing President George W. Bush needs. And so, when Beijing asks Mr Bush to look the other way on the Taiwan question, what is a besieged president supposed to do?

But the prospect of a conservative president going "wobbly" on Taiwan would not play well in the Republican trenches in Congress. And it would scarcely square with the administration's global policy of expanding democracy, which presumably was a key reason for the Iraqi operation. Taiwan, after all, is a democracy; mainland China is not.

But, again, if Mr Bush were pushed on Taiwan, what would he do? It may not be too long before the world finds out.

Tom Plate, a member of the Pacific Council on International Policy, is the founder of the Asia-Pacific Media Network.

Distributed by UCLA Media Centre