CATASTROPHE, as is the natural order of things, brings out the best in most humans, and the worst in some. When Katrina struck the US Gulf Coast this week, the first images reflected man’s instinctive compassion, heartening tableaux of daring rescues and selfless giving.

Then, of course, came the looting, the inevitable exploitation of misery that contributes the insult of human depravity to the injury of natural disaster, a piteous reminder that in the race to the bottom, even the most heinous of the elements are no match for the baser instincts of Man.

This duality has its counterpart in the response beyond those immediately affected: around the world expressions of sympathy and offers of help poured in. And then came the predictable exploitation of the tragedy for political purposes, the dishonest advancing of an ideological agenda. This represents a sort of intellectual looting, in which the perpetrators help themselves selectively to convenient facts for their own delectation, sidestepping the dead and dispossessed before making off with their meretricious spoils.

In Katrina’s case, the intellectual looters have busied themselves with plundering half-truths and false analyses to advance one of their most precious agendas: global warming.

The German Environment Minister, Jurgen Trittin, was first, with a claim that this was a real-life version of the shock-flick, The Day After Tomorrow. Sir David King, Tony Blair’s chief scientific adviser, weighed in, saying global warming was increasing the risk from hurricanes. Robert F. Kennedy Jr, self-designated leader of the American environmentalist cause, said the US was reaping the failure to sign up to the Kyoto Protocol. And, of course, Cindy Sheehan, the bereaved mother of a US soldier who leads the antiwar campaign and any other left-wing cause that wants her, noted President Bush was “heading to Louisiana to see the devastation that his environmental policies and his killing policies have caused”.

Best of all, though, was the contribution of Jon Snow, enthroned as the objective voice of British media at Channel 4 News, who chortled: “How ironic that the world’s No 1 polluter is now reaping the ‘rewards’ that so many have warned would flow.”

The only fitting response to that statement is a moment’s silence to reflect on the mendacity and inhumanity of it. But the problem with these claims is that, delivered ex cathedra to credulous audiences, they quickly become received wisdom, so we must take a moment to incinerate them.

There’s no evidence, in fact, of any increase in either the frequency or the intensity of hurricanes since Man has been polluting the atmosphere. The US National Hurricane Centre says that an average of 19 hurricanes hit the US landmass each decade in the second half of the 19th century. In the second half of the 20th century, the average was 14. In the first half of this decade, the US is precisely on course to meet the stable average frequency of the most serious hurricanes (Category 3, 4, and 5) of the past 100 years.

“There have been no published studies that argue for attributing an observed increase in hurricane intensity or frequency to global warming,” says Roger Pielke, director of the University of Colorado Centre for Science and Technology Research Policy, on his website. The Intergovernmental Panel on Climate Change, the same one that has been aggressively urging action to address climate change, concluded the same thing in 2001.

The real irony, in fact, is that this eagerness to apportion blame where it does not belong overlooks some more salient potential political implications of the tragedy of Katrina. Though it is early, some of the contours of these implications are coming into view. This is another time of trial for President Bush and in truth, he hasn’t fared well so far. His initial response has been inadequate, rhetorically and politically. His first speech to the nation, delivered not long after the nation watched him bound jauntily down the steps of Marine One, cradling a favourite pooch, was uninspiring, a self-congratulatory stroll through the Administration’s magnificent rescue efforts so far.

Mr Bush has time to recover from this stumbling inadequacy, as he did after his first response on September 11, 2001, and he needs to, given the press of other political problems he faces.

But there will be searching questions about the preparedness and the response of US authorities that will not be easily answered. Why was one of America’s most densely populated areas left so vulnerable for so long to such a predictable disaster? Why was there not a better co-ordinated plan than simple exhortations to people to get out of town? Above all, why has the federal Government, with all the resources at its disposal, seemed so dilatory? New Orleans has had four days to descend steadily into desperation and lawlessness, and the Government seems to have let it do so.

The biggest political question, though, may be about something that goes much closer to the very nature of American society itself; the dread inequality that is the ever-present obverse of its successes. Romantics like to think of nature as indiscriminate in its fury. Rising water pays no deference to wealth, makes no concessions to poverty; mansions and hovels both crumple before hurricane-force winds.

But it’s not true and the awful reality in New Orleans is a sharp disabusing of that notion. The tragedy has been visited disproportionately, indeed almost exclusively, on the city’s African-Americans. The images from the city have been compared with natural disasters in sub-Saharan Africa; it is the faces of the victims as much as the scale of the destruction that underscores the comparison.

This massive disparity of suffering is bound to provoke a fresh controversy about race and class inequality, the great open sore of American society that bleeds profusely from time to time. The spectacle of tens of thousands of indigent blacks, apparently alone in being unable to save themselves from this horror, will surely make it weep anew.

gerard.baker@thetimes.co.uk

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