At last! The controversy is over. It turns out the "scientific" claims promoted for decades by whiny self-righteous liberals were a lie, a fraud, a con–and we don’t need to change after all. The left is humiliated; the conservatives are triumphant and exultant.

The year is 1954, and the "science" that has been exposed as a "sham" by conservatives is the link between smoking and lung cancer. Welcome to Tobaccogate, as Fox News would call it. The conservatives are championing professor Clarence Cook Little, who says he has discovered insurmountable flaws in the use of statistics and clinical data by "anti-tobacco" (and quasi-commie) scientists. The press reports the "controversy," usually without mentioning that Cook Little is being paid by the tobacco industry. A relieved nation lights up–and so, over the next few decades, millions of them die.

It is happening again. The tide of global warming denial is now rising as fast as global sea levels–and with as much credibility as Cook Little. Look at the deniers’ greatest moment, Climategate, hailed by them as "the final nail in the coffin" of "the theory of global warming." A patient study by the British House of Commons has pored over every e-mail from the Climate Research Unit at the University of East Anglia and interviewed everyone involved. Its findings? The "evidence patently fails to support" the idea of a fraud; the scientists have "no case to answer"; and all their findings "have been repeated and the conclusions have been verified" by other scientists. That’s British for "it was a crock."

Yet a startling amount of denialism now, like Climategate, travels across the Atlantic from my country–Britain–to the United States. Yes, I know our accents make us sound instantly plausible, but it’s time Americans knew who these Brideshead bull-scientists really are. Look, for example, at their doyen–a man named Christopher Monckton. He has been lauded by the Wall Street Journal, National Review and Rush Limbaugh for exposing the truth about global warming, and is used by the New York Times as a balancing voice against the claims of climate scientists. In fact, Monckton is an English aristocrat with no scientific training. He studied ancient Greece and Rome, and worked as a policy adviser for Margaret Thatcher.

Oh, and he claims he can cure HIV. Seriously. As journalist George Monbiot points out, Monckton has stated in writing that he is "responsible for invention and development of a broad-spectrum cure for infectious diseases…including…HIV." He is prone to such wild fantasies. He has stated that he persuaded Thatcher to use biological weapons in the Falklands War. He falsely claimed he is a member of the House of Lords and a winner of the Nobel Peace Prize. When challenged, Monckton has admitted to a weakness for telling "stories that aren’t actually true."

Yet this man is treated as a great debunker of climate science in the United States. So what’s his alternative scientific theory? In a speech in Minnesota last year, he explained it. "There is no problem with the climate," except that Greenpeace is "about to impose a communist world government on the world" and "you have a president who has very strong sympathies with that point of view." Warming is an excuse invented so that Obama can "sign your freedom, your democracy and your prosperity away forever," and give it all to "third world countries."

That’s the intellectual caliber of the most celebrated denialist. Yet when it comes to coverage of global warming, we are trapped in the logic of a guerrilla insurgency. The climate scientists have to be right 100 percent of the time, or their 0.01 percent error becomes Glaciergate, and they are frauds. By contrast, the deniers only have to be right 0.01 percent of the time for their narrative–See! The global warming story is falling apart!–to be reinforced by the media. It doesn’t matter that their alternative theories are based on demonstrably false claims, as they are with all the leading "thinkers" in this movement. Look at the Australian geologist Ian Plimer, whose denialism is built on the claim that volcanoes produce more CO2 than humans, even though the US Geological Survey has shown they produce 130 times less. Or Sunday Telegraph columnist Christopher Booker, who says the Arctic sea ice can’t be retreating because each year it comes back a little… in winter.

Many Americans assume that if a story has been in the news section of a reputable English newspaper, it has been fact-checked. One recent climate "scandal" that spread from Britain shows how these stories actually originate. In its most recent report, the Intergovernmental Panel on Climate Change–the umbrella organization of the world’s climate scientists–explained that 40 percent of the Amazon rainforest is at risk of dying if there is even a slight reduction in rainfall. This is true. It is the view of the most distinguished scientists in the field. The IPCC sourced this claim to a report by the World Wildlife Fund–when, in fact, it should have referred to a report by professor Dan Nepstad, whose work is mentioned only in passing by the WWF.

It was a minor footnoting error–but when a denialist blogger named Richard North noticed it, he announced he had found the IPCC making fake predictions. He tipped off the Sunday Times, owned by Fox king Rupert Murdoch. The newspaper’s journalists quoted Dr. Simon Lewis, a leading rainforest expert, who explained that it was a very minor mistake and that the core claim is accurate. The paper ignored the bulk of his comments and mangled his quotes to make it sound like he agreed that the IPCC had been talking rubbish–and ran the "story" under the headline "UN Climate Panel Shamed by Bogus Rainforest Claim." It gave credit for "research by Richard North." The story was then zapped all over the United States as Amazongate, and as a result millions of people are now under the impression that the Amazon is in no danger. The Sunday Times refuses to admit it made a whopping error–in a story that attacks the IPCC for supposedly making a whopping error.

And while the United States has been engaged in these fake rows, the world may have just crashed into one of the climate’s tipping points. For years, climate scientists have had a nightmare scenario. Buried in the hard Arctic permafrost is a massive amount of the gas methane, which causes thirty times more warming than carbon dioxide. There is more carbon in the world’s methane deposits than in every lump of coal and barrel of oil on earth. As the poles defrost, it becomes possible that all of this gas will be farted out into the atmosphere–and trigger catastrophic warming.

Over the past year, culminating this March, a series of major on-the-ground scientific investigations of the frozen methane have been published. The author of one, Professor Tim Minshull, explained: "Our survey was designed to work out how much methane might be released by future ocean warming; we did not expect to discover such strong evidence that this process has already started." If you hold a match to the ground, a great flash of methane-fire now bursts forth.

Looking back, the historian Allan Brandt said the conservative-corporate machine that conned people into thinking smoking was safe pulled off "the crime of the century." We are now witnessing the crime of the twenty-first century, using the same strung-out old script. In his smoky hell, Clarence Cook Little must be offering a little chuckle.

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