WHEREVER on the planet the President of the United States may go, he carries with him the burden of innumerable domestic and world troubles. Barack Obama on his nine-day Asian trip may feel some relief at escaping from one purely domestic affair, the health insurance controversy, but the relief is tiny compared with the weight of the world troubles he has to address on his journey.

Tomorrow he will be in China, the country above all others with which the United States has to "cohabit". A long-established great power meets an emergent (or rather, almost fully-fledged) great power. The stronger China grows, the greater the danger of friction. The two have to find ways of getting along.

The trip takes place against a background of speculation that the Chinese will revalue their currency. The Americans would like that. They would also like some indications of progress on human rights, but we can assume that Obama will take care not to offend his hosts.

In any case, human rights are only part of an enormous complex of problems which the rulers in Beijing -- or the next generation of them -- have to address sooner or later, and which make the domestic problems of the United States look pretty small.

Will Hutton described them in an excellent book, The Writing on the Wall, published in 2007. He argued that the Chinese model, seemingly untrammelled capitalism but under the domination of the Communist party, is unsustainable. It has to be replaced by the "Enlightenment" or Western model, governed by democracy and the rule of law.

If you were one of those rulers in Beijing, you might well argue that the present system works very well. For the first time in history, everybody has enough to eat. Chinese industrial production and exports are awesome, and so are Chinese savings. Trillions of those savings are invested in the United States.

Against these achievements one must set cheap labour, low productivity, and no human rights to speak of. People can be thrown out of their houses and off their land in thousands, to make room for a dam or merely at the whim of corrupt local government officials. Riots for ethnic and other reasons are common.

But there is a bigger Chinese problem, which is also an American and world problem, and which will form the subject of immensely important and difficult talks for Obama in Beijing and other Asian capitals.

Climate change is the greatest menace facing the planet. Scientists sometimes disagree on its causes and in their forecasts of its effects, but overwhelmingly they hold that, if left unchecked, it can destroy civilisation. We're all in this together.

Or are we? Next month will bring the Copenhagen climate conference. The prospects are not good. Indeed, so dim are they that Chancellor Angela Merkel has threatened to boycott the conference.

Obama has a special reason for anxiety. "Climate change denial" has become fashionable on the American extreme right. Along with such fanciful theories as "intelligent design" goes a refusal to accept that global warming is man-made and even to concede the easily verifiable fact that the Arctic icecap is shrinking. And the refuseniks have their allies in the US Senate and House of Representatives.

So the President has to fight on two fronts: to get measures on carbon emissions accepted at home, and to persuade the Chinese and other "emergent" economies to co-operate abroad.

And he is up against a simple argument, which anyone can understand and with which anyone can sympathise. Along with India, China (which now has the world's biggest carbon emissions) asks why, and on what terms, it should reduce emissions. Have these countries not the right to try to catch up with the West? After all, the West built up its production and its wealth on coal and oil.

Most likely these questions will be resolved, in time, by such measures as nuclear power for electricity generation and cleaner fuels for vehicles. But how much time have we got? Most scientists say, not much. They don't think we can afford to wait for a new set of rulers in Beijing or anywhere else.

For the moment, we must assume that Obama's discussions in Beijing will result, at worst, in some sort of agreement and some pretence of progress. The Sino-US rapprochement has been described as America's "most important bilateral relationship", and neither wants friction at this time.

But where does that relationship leave everybody else? Specifically, where does it leave Europe, now that the United States and China are more powerful than all the former European empires put together?

Europe, so much more vulnerable than either of those giants, must have a say in the climate change debate. Angela Merkel will not help the cause by staying away from Copenhagen.

And neither will the cause be helped by the mindset that spurred the antics in Ireland, the Czech Republic and Poland surrounding the Lisbon Treaty. In Ireland in particular, these were the antics of people who simply did not take the issues seriously. As it happens, one of those issues was climate change, but it was scarcely mentioned during the referendum debates.

We can't tell the Americans or the Chinese what to do. But we can play a small part in building up a unity that will help Europe to face climate change and a myriad other issues.

We could start by taking an interest in the race for President of the Council and High Representative for Foreign and Security Policy. You can bet your life Obama knows who the candidates are. And so do the Chinese leaders.

Irish Independent