First, the facts: the US and international scientific community overwhelmingly agree that carbon dioxide emissions are triggering a slate of harmful effects on the planet.
"Climate change is occurring, is very likely caused primarily by the emission of greenhouse gases from human activities, and poses significant risks for a range of human and natural systems," declared a recent report by the US National Academy of Sciences. Of course, a small percentage of scientists disagree, as is the case with, say, evolution.
Yet, unlike their counterparts, climate truthers aren't merely an irrelevant group of rabble-rousers.
On the contrary, the scientific consensus is denied by the leaders of one of America's two great political parties, as well as the majority of its ideological base. John Boehner, the most powerful Republican in the country, considers the notion that carbon emissions are harming the planet "comical".
In recent years, this belief has become something of a GOP litmus test, and today, it's difficult to find Republicans who accept the scientific community's view.
Climate trutherism embodies the lynchpin of most conspiracy theories: the belief that a group of influential people is coordinating a wide-ranging cover-up to advance their interests by bamboozling the rest of us.
Doubting human-caused climate change requires the same paranoid logic as, say, doubting that the 9/11 attacks caught Bush officials by surprise, or that President Obama's birth certificate is authentic.
But rather than believing that we're being lied to by the Bush White House or Obama's mother and the state of Hawaii, you're required to believe that we're being lied to by nearly every scientist and scientific institution in the world.
So why, then, aren't climate truthers relegated to the fringes, alongside their brethren?
First, climate truthers have the support of a wealthy, powerful industry dedicated to mainstreaming their theory. Second, the Republican party's anti-regulation policy agenda is threatened by the realities of climate change, so it's better to deny there's something wrong than cede that argument to their adversaries. And third – and this is why it self-perpetuates – the media like to stay in good odour with powerful politicians, so often can't quite bring themselves to pronounce one side unequivocally wrong.
But as with all other conspiracy theories, it is the media's job to call them out as wrong and resist the urge to "split the difference".
If not, we'd be living in a society where 9/11 truthers and Obama birthers were legitimate sceptics, rather than outlandish people unable to come to grips with reality.
Yes, it takes more courage to call out climate truthers, because some of them are very influential.
But that's why it's more important – because climate change is relevant to our lives and futures in a way that the baseless speculation about Trig Palin's birthmother is not.