Updated

And so the great global warming circus moves on. For the next two weeks the world’s carboncrats will gather in Cancun for the latest United Nations climate conference. The aim is to negotiate a vast new international emissions trading scheme that Barack Obama wants the United States to join.

But the delegates are in a state of severe, almost clinical, denial if they think they will sign a legally binding and genuinely global agreement to slash greenhouse gases. Al Gore’s moment has come and gone.

For one thing, the political climate has changed dramatically in the past year. Opinion polls suggest the public in many nations has become more sceptical about global warming science. For example, one BBC survey found that only 26 per cent of Britons believe that “climate change is happening and now established as largely manmade.” A poll by the German magazine Der Spiegel showed that only 42 per cent of Germans feared global warming.

Indeed, the climate has changed so dramatically that former British prime minister Tony Blair – one of the most respected establishment voices urging fast action on climate change – mentions the subject only eight times in passing in his 700-odd-page memoirs.

In her 5,500-word keynote address to the Australian Labor Party campaign launch in August, Prime Minister Julia Gillard dedicated just one sentence to climate change, lest her energy tax proposal alienate her party’s working-class voters who are mortgaged to the hilt. The point here is that politicians all over the globe are either reconsidering the Kyoto-style costs of carbon taxes and binding targets (think Canada’s Stephen Harper) or trying to get controversial climate laws passed by stealth (think Australia’s Gillard).

Nowhere have the political winds shifted so dramatically than in the United States. When he won the Democratic presidential nomination in 2008, Barack Obama said: “We will be able to look back and tell our children that this was the moment when the rise of the oceans began to slow and our planet began to heal.” And he pledged to cut U.S. emissions 80 per cent below 2005 by 2050.

Two years later, however, his administration has ditched plans for an economy-wide cap-and- trade scheme. The Senate, with a super majority of Democrats, could not even debate an energy bill so weak that it consisted of little but loopholes to those big polluters. Pew surveys show that climate change ranks 20th as a policy priority among Americans. Only two of the 48 Republican contenders for this month’s senate elections said they believe in man-made global warming.

Even Democrats from Midwest coal-mining states recognize a low-carbon economy means a high energy-cost economy. Who could forget Joe Manchin’s campaign commercial during the recent midterm election? The West Virginia Democrat literally shot Obama’s cap-and-trade legislation with his hunting rifle.

To be sure, the president could use the Environmental Protection Agency to override Congress and unilaterally impose regulations under the 1990 clean-air laws. But such action would be deeply unpopular in several bellwether, recession-plagued states in the run up to the 2012 presidential election. In any case, executive regulation would almost certainly be tied up in litigation.

Which brings us to another reason why a global deal is not feasible: the economic cost of decarbonizing the global economy is massive and would outweigh any benefits it may conceivably bring from any cooling of the planet.

The Chinese, already the world’s largest emitter of carbon dioxide, and the Indians, catching up fast, recognise this fact better than anyone. After all, their overriding priority is to grow their economies and reduce poverty, malnutrition and disease – and the cheapest source of doing all this, at least for the foreseeable future, is carbon energy.

Many environmentalists praise Beijing for heavily investing in renewable energy and cleaning up its coal-fired power stations. But China is still chugging along the smoky road to prosperity and its carbon emissions are steadily increasing. As for India, it will undertake mitigation efforts if it is in its self interest.

The upshot is a never-ending, circular argument that goes nowhere: every nation will keep blaming every other nation for the collapse of talks; and every nation will keep insisting that every other nation should move first and slash emissions.

Get ready for another Copenhagen in Cancun.

Tom Switzer is a research associate at the United States Studies Centre at the University of Sydney and editor of the Spectator Australia.