"We want to be in (the new UN climate pact), we want to be pragmatic, we want to look at the science," said Jonathan Pershing, the head of the U.S. delegation, during the talks on cutting greenhouse gas emissions in Bonn last week. So how will the Obama administration reconcile political "pragmatism" with the scientific realities?

"There is a small window where they overlap. We hope to find it," Pershing explained. But it doesn't really exist.

Signing the United States up to the new climate treaty that will replace the Kyoto accord in 2012 is essential. The 1997 Kyoto treaty was gutted to accommodate American objections, but even so President Clinton, who signed it, never dared to submit it to Congress. Then President Bush "unsigned" it.

A dozen wasted years later, the climate problem has grown hugely, so this time everybody else is determined that the U.S. must be aboard—and Barack Obama also wants the United States to be part of the treaty. But we recently learned what he thinks is "pragmatic". It is that the United States should cut its emissions back to the 1990 level by 2020.

"Pragmatism" is the excuse you use when you do less than you should, because doing more is too hard. Taking a dozen years just to get back U.S. emissions back down to where they were in 1990 definitely qualifies as "pragmatic", but it also qualifies as suicidal folly.

The Hadley Climate Centre in England, one of the world's most respected sources of climate predictions, recently released a study showing that even rapid cuts in global greenhouse gas emissions, turning the current one percent annual growth into a three percent annual decline within a few years, would still warm the world by 1.7 degrees Celsius by 2050.

That is dangerously near the two degrees Celsius rise in average global temperature that is the point of no return. Further warming would trigger natural processes that release vast quantities of greenhouse gases into the atmosphere from melting permafrost and warming oceans. These processes, once begun, are unstoppable, and could make the planet four, five, or six degrees hotter than the present by the end of the century.

At those temperatures, much of the planet turns to desert, and the remaining farmland, mostly in the high latitudes, can support at best ten or 20 percent of the world's current population. That is why the official policy of the European Union is never to exceed two degrees of warming.

The Obama administration's offer falls far short of that goal. Under the Kyoto accord the U.S. promised a seven percent cut on 1990 emissions by 2012, but President Bush abandoned that target and American emissions are now 16 percent above the 1990 level. President Obama is only promising to get back down to the 1990 level over the next 11 years, and forget about the further cuts that the U.S. signed up to a dozen years ago.

Obama is clearly calculating how much he can get through Congress. As Pershing said in Bonn, "If we set a target that is un-meetable technically, or we can't pass it politically, then we're in the same position we are in now— where the world looks to us and we are out of the regime."

But this isn't an ordinary bill where you settle for what you can get through Congress after the usual horsetrading. If there's going to be a 40-day flood, you either build an ark or you learn to breathe underwater. Building half an ark is not a useful option.

Obama's offer means that the United States would be cutting its emissions not by three percent annually, the minimum global target if we hope to avoid more than two degrees of warming, but by only half that amount. In the long term, it leads inexorably to disaster.

The other two major delinquents among the industrialized countries are following similar tactics. Australia, which had long been in denial about climate change, ratified the Kyoto accord after the 2007 election, but the new government is offering emissions cuts of only between five and 15 percent by 2020. That is a target that makes even Obama's offer look good.

Canada, which ratified the Kyoto accord long ago and promised a six percent cut in emissions by 2012, simply ignored its obligations and is now 20 percent above its 1990 level of emissions. It has no intention of trying to make up the lost ground, and has unilaterally moved its benchmark from 1990 to 2006.

Most other industrialized countries are on track to meet or exceed their modest Kyoto targets. Britain and Germany will both be 20 percent below their 1990 emissions level by 2012, and Germany is promising 40 percent cuts by 2020. The European Union as a whole promises a 20 percent cut by 2020, but will go up to 30 percent if other industrial countries do the same.

Even that would barely meet the annual three percent cut in emissions we need if we are not to sail through the two-degree point of no return and trigger runaway warming. And we have yet to figure out how to bring the rapidly developing countries into the regime, for their emissions, though starting from a low base, are growing very fast.

We are in deep trouble, and "pragmatism" will not save us.

Gwynne Dyer is a London-based independent journalist whose articles are published in 45 countries.