Truth deniers — or is that what they want you to think?

Conspiracy theories multiplied when the internet era began because they allow believers to think they are a part of a heroic group who see past official versions, says Donal O’Keeffe.

A leading British academic has warned that a new internet-based generation of Holocaust deniers is emerging through “gateway” conspiracy theories.

Professor Nicholas Terry, a history lecturer at Exeter University, has spent the past decade studying the spread online of Holocaust denial.

Holocaust deniers are on the rise, thanks to other conspiracy theories.

He says new deniers come now not just from far-right online forums but also via conspiracy theories such as those surrounding JFK, 9/11 and the moon landings.

Terry’s warning coincides with the Irish release this weekend of the film Denial, which dramatises the libel case taken by the Holocaust denier David Irving against the American historian Deborah Lipstadt and her publishers Penguin Books.

Deborah Lipstadt.

Terry told The Guardian that “the internet creates a milieu that has seen people who would normally identify along the left of the political spectrum gravitate towards ideas that are more at home on the far right.”

A friend told me recently she hates Hillary Clinton because Clinton is part of “what George Soros and the Jews really did during World War II”. When I pointed out Soros was 15 in 1945, by which time the Nazis had murdered over six million Jews, I was dismissed as “listening to Mainstream Media”.

David Aaronovitch’s Voodoo Histories: The Role of the Conspiracy Theory in Shaping Modern History (2010) debunks some of the most popular conspiracy theories and asks why well-educated, reasonable people sometimes believe “perfectly ridiculous things.”

Aaronovitch looks at key common characteristics of conspiracy theories. They tend, he says, to be politically populist, paranoid and granted a veneer of respectability by selective quotations from often dubiously-qualified academics (“death by footnote”) and authentic-sounding jargon like “false flag”, “wet-works” and “psy-ops”.

Conspiracy theories usually claim to lay bare the actions of a small power elite. Belief in the conspiracy makes you part of a heroic group who can see past the official version propogated by the powers that be. Those who cannot or will not see “the truth” can be dismissed as “sheeple”.

Conspiracy theories tend to be impervious to logic. Pre-internet, Deborah Lipstadt likened arguing with a Holocaust denier to trying to nail jelly to a wall.

“It’s now like trying to nail smoke to a wall,” says Nicholas Terry. “There’s almost no substance.” Most conspiracy theories are harmless but some have calamitous real-life effects.

Mercifully, no one died last month when Edgar Maddison Welch fired an AR-15 assault rifle in a Washington pizzeria. Described by friends as “well-meaning”, Welch had read online that the restaurant was headquarters to a global paedophile ring headed by Hillary Clinton.

Edgar Maddison Welch said he was investigating Hillary Clinton running a child sex ring out of a pizza parlour.

Adolf Hitler loved the “Protocols of the Elders of Zion”, a 1903 anti-Semitic forgery which popularised the notion of a worldwide Jewish conspiracy to control press and banking. The historian Nora Levy said “Hitler used the Protocols as a manual in his war to exterminate the Jews”.

The high-ranking Nazi Erich von dem Bach-Zelewski later admitted that there was no Jüdische Gefahr (“Jewish Menace”).

“In reality, (Jews) had no organisation at all, not even an information service,” he said. “If they had had some sort of organisation, these people could have been saved by the millions, but instead, they were taken completely by surprise.”

To this day, the theory of a global Zionist conspiracy (overlapping with Holocaust denial) is accepted as an article of faith in much of the Middle East.

With conspiracy theories, David Aaronovitch instances Occam’s razor, where the simplest explanation is usually true, but he also cautions against credulity.

“You can’t just assume right from the beginning that any conspiracy theory is automatically wrong because it seems to violate common sense. You have to go back to first principles and say ‘What is the evidence for this?’”

Children look at a model of an alien on display inside the International UFO Museum in Roswell in the US.

Are there aliens in Roswell? If there are, perhaps Nixon should have asked them to hide Watergate, which really was a conspiracy and which ended up costing him his presidency.

Were the moon landings faked? Imagine how many thousands - not just the dozen astronauts - would have had to maintain a lifelong silence for that.

The 9/11 attacks attract plenty of conspiracy theories.

Did Dubya Bush stage-manage 9/11? If so, it was a masterstroke to have the most powerful man in the world reading “The Pet Goat” as the skies fell.

Is our Government fluoridating water to control our minds? If they are, it’s amazing we haven’t paid our water charges.

One current conspiracy theory - that Russia interfered in the US presidential election - typifies our post-truth world, where fact is a multiple-choice proposal. It was a conspiracy, according to every US intelligence agency. Donald Trump, who would have benefited from such interference, says that’s just a theory.

There really are conspiracies. It’s just we’re not very good at keeping secrets and real-life conspiracies tend to fall apart. “Three may keep a secret,” Benjamin Franklin said, “if two are dead.”

Or maybe that’s just what Mainstream Media wants you to think.