Nothing, it seems, is as it seems. My generation thought that Jimi Hendrix was just another of our tragic self-culled heroes, alongside Janis, Jim, Keith, Brian and Marc. This weekend I learnt from James “Tappy” Wright, an ancient roadie who has a new book out, that Jimi was actually murdered. Some time in 1971, a year after Hendrix died, his manager — one Mike Jeffery — in his cups, confessed to Wright that he had done the superstar in.

“I was in London the night of Jimi’s death,” Jeffery had told Wright, “and together with some old friends, we went round to [the] hotel room, got a handful of pills and stuffed them into his mouth . . . then poured a few bottles of red wine deep into his windpipe.” It fooled the pathologist and the coroner and Jeffery walked off with Hendrix’s money and a large insurance policy.

Alas, Jeffery has not been in a position these 35 years to confirm, deny, sue or indeed do much of anything following his 1973 air crash. Wright’s explanation for his own inordinate delay in setting the record straight is that Jeffery’s friends might have sought retribution, so we must presume that these shadowy persons are now also beyond exacting revenge. Perhaps he will name them. Myself, I can’t help thinking that (a) the method of murder described above is a little hit and miss, and (b) that Jeffery’s probably being in Majorca on the night of the death is problematic. I ask myself whether it is more likely that a rock star didn’t really die of drugs and drink, than that Wright is a fabulist selling a book. I mean, which scenario is the most common in our experience?

Same day, and we travel to Austria to discover that far-right politician Jörg Haider, widely believed to have died in an alcohol, tiredness and speed-induced car smash last October, might in fact have been the victim of a plot by persons unspecified (but likely to include the Austrian Government, the CIA and, I daresay, Mossad). We are told that an “investigative reporter”, Gerhard Wisnewski, has written a book entitled Jorg Haider: Accident, Murder or Assassination, claiming that the wreckage of the car shows suspicious marks and holes, that there was alcohol in his blood but not in his stomach (which is supposed to be odd), and that it is suggestive that Haider’s 2.5 tonne vehicle was an almost complete write-off.

Parts of the Austrian Right, including Haider’s wife, have seized on the contents of the book and are demanding an inquiry. There is, after all, a big political difference between a martyred hero and a drunken roadhog. In our own online comments section under the story, one may find Paul from Klagenfurt in Haider’s Carinthia invoking the Freemasons. Rick from Newcastle opts for Mossad, but doesn’t say why.

My difficulty was that I recognised the name of Gerhard Wisnewski. Knowing he had already written two books on the 9/11 “myth”, one on how the Red Army Faction was an inside job, and another entitled One Small Step? The Great Moon Hoax and the Race to Dominate Earth from Space, I couldn’t really see him coming up with a tome in which the answer was “accident”.

But it’s good fun, isn’t it? Really? Jeffery is dead, and can stuff like this be of any help to the Austrian far Right? It’s like those ludicrous programmes on Iranian official TV in which various “experts” and documentary-makers uncover the hidden message in Hollywood films. Meet the Parents, for example, is a cunning attempt to make the moviegoer sympathise with the put-upon Jew. Harry Potter is a tool that “serves to spread the dark and evil essence of Zionism and its goals”. Because the Zionists “are trying to convince viewers that because there is no easy way to distance oneself from witchcraft, Satan and the like . . . they are saying indirectly, ‘Join us’ ”. One wonders what “J.K.” in J.K. Rowling really stands for. “Jews Know”, probably.

Laugh? Someone else nearly died. Then you get a serious bit of unrest, a clamour against authoritarianism, a desire for autonomy and the conspiracy theory takes on a different shade. Since you live in Paradise full of happy people, the effort to subvert it must come from outside. Yesterday’s Uighur riots in China are all down to an exiled businesswoman called Rebiya Kadeer, according to China’s officials. And last month’s Iranian protests were drummed up by the Brits, say the spokesthings of the theocracy.

On Sunday alone the Iranian police chief said that the “BBC and the British Embassy spearheaded efforts aimed at provoking unrest and incited people to commit civil disobedience”; the judiciary chief ordered actions against foreign satellite channels “working against Iran” and threatened action against those co-operating with such channels; the head of Iran’s electoral office said that the country’s post-election unrest had been planned by Western elements months earlier.

Before that, a chief of the official Fars news agency charged the BBC with “psychological warfare”; a conservative newspaper accused the BBC’s correspondent Jon Leyne of himself setting up the fatal shooting of young Neda Agha-Soltan in Tehran, while Iran’s Ambassador to Mexico blamed her killing on the CIA. Most ominously, demonstrators bearing obvious bruising have “confessed” on television to having been influenced by the BBC and American news channels.

The drift of the pro-theocracy conspiracy theory is clear, and it bears similarities to the great Trotskyite conspiracy theory disseminated by Stalin between the Thirties and early Fifties. All those industrial accidents? Sabotage! All that grumbling? Plot! So the Iranian Government takes dissent — or even the possibility of dissent — and by waving the wand of conspiracy over it, turns it into treason. And if you believe that the world works that way, and that Ben Stiller is a Zionist shill, then it isn’t so far-fetched.

Maybe it will work, but maybe it won’t. On the website of Press TV, the Iranian English-language channel, most anti-regime comments are edited out. But some survive for a day or two. A regime apologist writes in to tell dissidents they have become “pawns in Evelyn Rothschild’s deadly little game against the Iranian people and Islamic Republic”. One replies, “That is funny! We who are grief stricken and in horror over what the Iranian government has done are puppets manipulated by someone named Evelyn? Do you drink??”

David Aaronovitch is the author of Voodoo Histories: The Role of the Conspiracy Theory in Shaping Modern History (Jonathan Cape)

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