Princess Kate conspiracy theories are vicious and hurtful - there's a far more simple truth, says Nigel Nelson

Even when she does appear in person on a shopping trip in Windsor the conspiracy nerds say it’s not her but a doppelganger. If royal protocol allowed, she should raise two fingers on her next outing to show what she thinks of them. That's what Rishi Sunak would like to do to his MPs, too.

Other conspiracy theories, such as the moon landings were faked and Princess Diana was murdered by MI6, pick up a larger following. Even Liz Truss believes she was ejected from No10 by deep state agents in the...Economist and Financial Times.

I know journalists on both titles. Double-0-sevens they are not.

At one time or another 25 per cent of Brits have bought into the theory US astronauts never set foot on the moon. According to one version, the hoax was staged by Hollywood with the help of Disney special effects relying on a script by Arthur C. Clarke and directed by Stanley Kubrick.

Had this been even remotely possible I wonder what the working title might have been? A Clockwork Blancmange?

Yet without persuasive evidence to the contrary, the most straightforward answer for a cause and an effect is usually the one which is most likely.

As a British Intelligence officer once told me, it would have taken a lot of people and a lot of organising to arrange Diana’s assassination. Someone, troubled by their conscience, would surely have blown the whistle by now.

Which makes it exactly what it seemed - a tragic accident in a car speeding too fast through a Paris tunnel.

There were 400,000 people working on the Apollo moon project who came and went over a period of 10 years. It defies rational belief that all of them would have kept their mouths zipped if they had just been beavering away on a movie.

That does not mean there are no conspiracies, but most are embarrassing failures rather than sophisticated successes.

Yes, some dimwitted Tory MPs do think they can topple Rishi Sunak and replace him with Penny Mordaunt and her sword to give them a more cutting edge election campaign.

Yet, when I asked trusted contacts around the Commons yesterday how seriously this was being taken the replies were a variation on spherical objects.

Even if MPs could pull off such a coup they would be crackers to think they could do it without prompting an immediate general election.

The PM, with nothing more to lose, might call one himself. And if he didn’t, the clamour from the public outraged at being lumbered with a third PM without their consent would surely force one.

Covid conspirators come in all sorts and their beefs range from rare to overdone. The disease was no worse than a mild touch of flu. Lockdowns were an excuse for Governments to control us. The vaccine kills people.

The Office of National Statistics says in the eight months from the first 2020 lockdown 394 people died of flu and 48,000 from Covid. Think about that ultra low flu figure for a sec. Does that not suggest lockdowns prevented infections?

ONS figures from last year show 51 deaths in which the Covid vax was the underlying cause. That means a one in three million chance of croaking from a single jab compared with 1 in 100 odds of dying from the disease in the first wave.

Yet when I quote those figures to conspirators, they say the true vax death toll is being covered up. ONS wonks are the last people to try to hide stuff. They love nothing more than to bore with their statistics. Get one on the phone and you’ll never get them off.

That is not to say mistakes were not made - the silly tier system, for instance, and discharging the elderly from hospitals into care homes without testing. But in nearly four decades of covering the British Government, its capacity for unforgivable mistakes was, dispiritingly, what I came to expect.

But they are cock ups. Not conspiracies.