While Maurice Newman drew inevitable criticism for his insistence that climate change was merely a cover for an agenda to establish “a new world order under the control of the UN”, there’s a certain rigour to his views.

The problem for climate denialists, who are almost uniformly older, white, male and conservative, is the sheer weight of evidence that our climate is changing in accordance with the predictions of climate scientists, and the fact that climate scientists are nearly unanimous in their views of anthropogenic global warming. There comes a point when all the cherry-picking, wilful misinterpretation and invented, blog-sourced “data” is simply not enough to explain the preponderance of evidence. Many climate denialists aren’t stupid — they’re often men who’ve been highly successful in business or politics and who are well-educated. The weight of evidence thus poses a dilemma, because to accept anthropogenic global warming is, for them, to accept something they associate with their political, economic and cultural enemies, to allow their much-hated opponents a win.

As a result, many, such as Newman, resort to conspiracy theories. Indeed, climate denialism must inevitably default to a conspiracy theory, because nothing else can explain the wealth of evidence about climate change except that it is being manufactured as part of a vast left-wing conspiracy. Nothing else can explain why there is so much evidence for climate change, and why so many experts insist it is real, than the fact that they are part of a giant plot.

This is why Barnaby Joyce joined in with the conspiracy theories yesterday, agreeing with climate wacko Andrew Bolt that the CSIRO and the Bureau of Meteorology were “warmist institutions” aiming to “get your money and put it in [their] pocket and send reports backwards and forth to one another.”

It’s a little bit different to Newman’s conspiracy, but there’s a typology for these things. The likes of Barnaby Joyce believe that climate change is invented by science organisations in order to provide a justification for higher taxes, the revenue of which will flow to them. For Newman, as for many other hard-right conspiracy theorists, the plot is altogether vaster, and includes not just the world’s climate scientists but the United Nations, most of the world’s progressive political parties, large sections of the Western media and a huge array of other organisations dedicated to the goal of imposing a single government on the planet.

That the United Nations — one of the world’s most inept bureaucracies that is incapable of even basic, piss-up-in-a-brewery type organisation — should be the vehicle for this global takeover is not the funniest thing about that particular conspiracy, it’s that several tens of millions of people are part of it and yet all stay resolutely silent, preserving the omerta of the climate change mafia. Like chemtrails, fluoridation, gun control, antivax and 9/11 conspiracies, Newman’s UN theory falls down in its reliance on a ludicrously unrealistic capacity for organisation and confidentiality by governments. In conspiracy theories, governments always operate with ruthless efficiency, no one ever makes a mistake and no one ever blabs about what’s really going on — that is, they operate in a way that anyone who has ever worked in a bureaucracy could only wish they did. Newman’s one world government thesis relies on this, but expands it dramatically to involve far more people far more countries and far more languages.

Newman might have been better off going for Joyce’s less ambitious greedy-scientists theory — or perhaps even one of the rarer theories, like that climate change is a fiction invented by the nuclear power industry to revive its fortunes. The UN global conspiracy theory is Illuminati stuff, the sort of thing that tends to involve blokes in aprons with secret handshakes, obscure Templar rites and Holy Grails.

The problem for the government is that Newman is head of the Prime Minister’s Business Advisory Council. If Newman had warned that fluoridation was a plot to poison our precious bodily fluids, or that aircraft contrails were streams of aerially distributed poisons (to do what, it’s not quite clear, but anyway) or that there was an entire underground civilisation living within the earth, with the entrance deep in the Arctic, he wouldn’t have lasted in that role five minutes. But only within the old white male conservative ranks of the Coalition are Newman’s ravings not considered on par with the delusions of antivaxers, 9/11 truthers and other internet nutjobs.