That strange belief logically follows from their continuing belief in the equally strange - and scientifically disproven - axioms of Victorian Era science.
They are, in a phrase, "People of the First Law" , when the 21st century's leading (tenured/peer-reviewed) basic scientists are all "People of the Second Law".
Thermodynamics , dear Watson : the two sides of the climate change debate are fighting over nothing more than the human consequences of assigning differing priorities to the two Laws of Thermodynamics !
Majority of deniers think Watermelons, not Jewish families, are behind Climate Change
Some deniers may think that conspiracy group consists of old world Jewish "banking families", but the vast majority of deniers think the actual group planning a world takeover on the backs of a bogus claim of a warming planet are the so called "watermelon conspiracy".
After "Our Side" won the Cold War in the early 1990s, deniers explain, "The Red Side" (not at all to be confused with the Red States - they are the good guys) cheated by just pretending to accept defeat.
But what it actually did was paint a new colour all over itself by expressing a sudden new "green" interest in saving the environment while still secretly planning to dominate humanity via a One World Government scheme, based on old "red" socialist-communist values.
Voila ! "The Watermelon Conspiracy" : green on the outside and red on the inside.
Hence the election of Obama-the-birther, some deniers claim ( shout out to the Viscount !), because "we all know how them there colored boys love ther watermelon".
Along with straight razor fighting and beatin' their gal : yep, its the Era of "The Coon Song Redux" .
And why not ? Because the science of the deniers is also from that long ago era of more than a century ago - might as well be consistent.
Belief in the priority of the First Law of Thermodynamics sees nature as a largely static backdrop to the dynamic activities of humanity : the climate literally can't change, can't do more than merely oscillate within a narrow range, back and forth or up and down, around a fixed, eternal, central equilibrium.
If you are over the age of sixty and took any geology in your science education at high school or university, you might recognize this as geology's all-ruling DOGMA, until very, very recently : Sir Charles Lyell's Uniformitarianism.
Expressed in slightly different forms, it dominated all science and in fact all human thought until well after 1945 and the uniformitarian debacle of WWII.
In mainstream Economics and in Darwinian Biology, this mid-Victorian scientific delusion still does dominate.
And of course, in the minds of the deniers. Most of them are old enough to have the genuine excuse of claiming that it was, after all, the cutting edge theory of its day at the high school where they last encountered the formal study of science.
With Nature passive and yet Reality highly active, believers in the First Law are almost forced to credit all change in the climate to just two things : a claim that these large and long term changes in our climate are in fact just temporary and local, if you view them from a long enough and distant enough perceptive, like that of say Simon-Pierre LaPlace in his executive suite high above the Universe.
Or that some group of humans, credited as a consequence of the First Law with virtually unlimited powers of will and mind power, have managed to fool all other humans into believing in a delusion : the delusion that the climate - and Mother Nature herself - can actually change.
Deniers sincerely - and consistently following from incorrect axioms - logically believe it is not they but the rest of humanity that is deluded.
As I have always claimed, all debate and all conflict is over initial axioms and nothing else......