RADIO 4 falling silent for a prolonged time is apparently a signal to British nuclear submarine commanders to open the Letters of Last resort, missives from the prime minister detailing what should be done in the event of a nuclear attack.

I wonder, incidentally, if Liz Truss had time to even get hers on board before she stood down. When a prime minister resigns, the Letters are destroyed without being opened. Imagine the four submarine commanders that had to bin Boris Johnson's instructions.

Of all the extravagant wastes of resources, there's another.

But rather than Radio 4 going off the air, it's being lit up with a far milder incendiary device yet one that speaks just as strongly to the fact of these extraordinary times.

That's now twice in 10 days that someone's seen fit to drop a swear word on the douce, respectable channel. A swear word!

If there was ever a sign of the rapid decline of Britain, of the tearing asunder of taken for granted rules of fair play, graft and decency, it's the F-bomb on Radio 4.

We had Miriam Margolyes letting it rip first. Then, across the channels, Krishnan Guru-Murthy.

There but for the grace of God, should have been the response from the bulk of the press when Channel 4 News's Guru-Murthy was caught calling the Northern Ireland minister Steve Baker a "c**t".

If it had been Glasgow, Mr Baker might have been flattered by the compliment but this was London, where such a word still packs a punch, and Guru-Murthy received the penalty of being removed from air for a week.

That's a word with its own reactions and foibles. You can say it in Scotland's largest city with impunity, not an eyelid batted.

I remember going to see a play about a Jewish family in Covent Garden years ago. The characters made Holocaust jokes that had me and my friend squirming with disquiet while no one else seemed at all fussed. Towards the end of the play one character called the other a "c**t" and the entire audience gasped, horrified, as one, while we looked around, baffled, to see what the problem was.

Not that we're strangers to swearing at politicians. In the more innocent times, when things still seemed like they might all be a passing lark, Johnson tried to dodge a journalist's questions by hiding in a walk-in fridge.

"For f***'s sake," his advisor snapped, live on camera, neatly summing up the mood of the nation.

Miriam Margolyes similarly summarised the national psyche when she took a sweary punch at Jeremy Hunt. She'd seen him at a party, she told the listeners of Radio 4, and had wished him good luck. Her preference, she went on, was to have told him to "f**k off, you b******d".

The presenters sounded like an electric shock had gone up them. Luckily it was the end of the segment and Ms Margolyes was ushered off, likely not hanging her head.

Emboldened, no doubt, by this example, on Saturday, a terribly politely spoken caller to Any Answers left Anita Anand reeling when she described the latest late prime minister thus: "I consider Miss Truss to be a puff in the wind. She's all fart and no s**t."

Ms Anand was not angry, she was disappointed. "We just can't talk like that," she said with her clipped vowels. "It's Radio 4, goodness me."

It's all context though. Ms Margolyes was the darling of social media and office water coolers both for saying what the public was thinking but also for the absolute brass ovaries of daring to swear on Radio 4.

It was quite delightfully wholesome, the reaction. Did you hear Miriam Margolyes? On Radio 4? Saying a Bad Word.

She gets away with it because people simply appreciated the sentiment. Also because of her age. Women get to a certain point in life where they can escape the sort of scrutiny focused on younger women, where cantankerousness is admired and forthrightness seen as a virtue.

There's no one but themselves that they need to please so their thoughts and tongues are their own.

It's enjoyable to watch, that power in profanity. Dame Helen Mirren once said that, had she a daughter, she would have taught her the first words "f**k off", that most flexible and delicious of swears.

This is different from, say, Lewis Capaldi blasting his way through the One Show and BBC Breakfast with a litany of swears. You can walk away from that without too much ruction.

But swearing on Radio 4? That's the collapse of society, there, the end of civilised days. If anything might make the Conservatives realise they've taken it all too far, it's that.

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