Ben Frisch was a geometry teacher in New York.
He was illustrating an obtuse angle in geometry class, using his stiff, outstretched arm.
As he noticed his pose, he said: "Haha, sorry, heil Hitler".
Big mistake, he made a joke.
Several of the rich Manhattan parents complained and he was sacked.
Despite the fact that he’d taught at that school for 34 years, and his Jewish grandparents had been killed by the Nazis.
But the parents were paying $45,000 in tuition fees for their children, and the head of the school decided that took priority over everything.
Anything that offended rich parents couldn’t be tolerated.
Despite the fact that 190 students signed a petition supporting Frisch.
Despite the fact that 469 alumni, who’d been taught by him, signed a similar petition.
Despite the fact that Philip Schwartz, who taught there for 48 years, asked for his name to be removed from the list of faculty members, saying: "The school is capsizing into the swamp of political correctness."
Recently, in Scotland, a man was fined £800 for posting a video online of his girlfriend’s dog, he’d taught it to give the same Nazi salute, to annoy her.
Big mistake, he made a joke.
The Airdrie Sheriff’s Court judged that a dog doing a "heil Hitler" salute was offensive.
The comedian, Jonathan Pie, makes the point that of course it’s offensive – to Nazis.
The one place that video would have been banned was Nazi Germany.
Where they would also have banned Mel Brooks singing "Springtime for Hitler", or John Cleese’s Nazi walk or all the online Downfall parodies with subtitles.
They would have banned them because they poked fun at the Nazis.
Gordon Smith showed me a picture of his dad in the Eighth Army, he was standing in the back of a captured German staff-car with his fingers under his nose and his arm straight out.
Obviously doing a "heil Hitler" salute.
My Uncle Harry had similar pictures, it was standard humour among the blokes who were fighting and killing Nazis.
They did it to take the piss out of Nazis. These were men who were risking their lives to fight Nazis, not just virtue-signalling.
They weren’t "offended" by Nazis, they were in a life-or-death, killing war. What helped was to make the enemy less frightening by poking fun at them.
They didn’t have a lot of rich parents threatening to sack them because they felt offended.
But that’s what we have today – PC warriors.
GK Chesterton said: "Puritanism is the pouring of righteous indignation into the wrong things."
Political correctness is the modern form of puritanism.
Oliver Cromwell was a puritan, he was offended by many things, as Lord Protector. He banned all forms of "pointless enjoyment" which he thought were bad for people.
He banned drinking, and theatres, and dancing, and pubs, and swearing, and football.
He banned colourful or revealing female dress, he banned make-up, he banned Christmas celebrations, and decorations.
After Cromwell died, the people dug his body up and hanged it at Tyburn.
And Cromwell’s head was cut off and displayed on a spike.
And everyone went back to drinking and singing and dancing, and all the things they’d done before Cromwell banned them.
It seems ordinary people just don’t know what’s good for them.
Dave Trott is the author of Creative Mischief, Predatory Thinking and One Plus One Equals Three