In 1946, the US tested the first peacetime atomic bomb.
They chose a deserted atoll in the Pacific.
Two French designers thought this was a great opportunity to launch their new two-piece bathing costumes.
Jacques Heim and Louis Réard both came up with the same idea, separately.
Until then, swimsuits had been one piece, never daring to expose a lady’s midriff.
Doing so would be such a shock, such a scandal, it would cause an impact like the US’s atom bomb test.
Heim got in first – he called his swimsuit the "atome" because it was tiny and it would cause shockwaves.
All the experts said it was the better name, it was a no-brainer.
The only choice Réard had left was the name of the place where the explosion happened.
It was on a small atoll, a lagoon, which was called "Island of Coconuts" in the local Ebon language.
Coconut was "pikki" and island was "ni", so the atoll was named Pikki-ni.
For simplicity, the Americans just called it Bikini atoll.
So Réard called his bathing suit the "bikini".
And amazingly it stuck.
Because everyone thought the "bi" meant two and "kini" meant teeny-weeny.
So "bikini" must mean teeny-weeny two-piece swimsuit.
No-one remembered it came from Pikki-ni.
And surprisingly no-one remembered the other swimsuit name: the "atome".
The one that all the experts thought was the far better name.
But marketing isn’t about what experts think, it’s about what ordinary people think.
Réard then marketed his swimsuit as the tiniest, with the line: "It’s not a genuine bikini unless you can pass it through a wedding ring."
It was so shockingly skimpy he couldn’t even find a professional model to pose in it.
He had to hire a stripper, Micheline Bernardini, to be photographed wearing it.
Such an erotic garment horrified the authorities, especially in the US.
In Hollywood, bikinis had to have a huge top half and a huge bottom half – in fact, they were shown in films with just a two-inch gap between the top and bottom.
The idea of showing a woman’s belly button was just too shocking, verging on porn.
Even in Beach Blanket Bingo – the 1965 rock ’n roll surfer movie with Frankie Avalon and Annette Funicello – the bottom half of the bikini always had to cover her navel.
But despite the authorities’ outrage, bikinis did become skimpier and skimpier.
Experts will tell you this was because men demanded women expose more flesh.
Actually the reverse is true – it wasn’t anything to do with men, it was women who wanted it.
Women didn’t want a two-inch band of tanned flesh just around their middle, they wanted a nice even tan all over.
And they didn’t care if it meant showing their belly buttons.
Because the bikini wasn’t actually a swimming costume at all.
The bikini was a new kind of garment, much better for women to sunbathe in.
The proof of this was that 80% of bikinis never went in the water.
Which is something else the experts got wrong.
But experts don’t care what actually happened.
They have to pretend to know what the public is going to think in future.
So they reinvent the past, or the future, based on what they know about the present.
Surprisingly, the thing experts really are expert at is finding people to pay for their opinion.
Dave Trott is the author of Creative Mischief, Predatory Thinking and One Plus One Equals Three.