ONE of the perks of being a former premier, alongside the choke-a-horse pension, is having the chance to raise a stink now and then. Not quite the pong left when a sacked reporter, posing as a house buyer, visited his ex-editor’s home and hid a packet of fish fingers behind the bath panel to rot – ah, Findusgate – but a decent enough stench will always draw the crowds and remind a former leader that they have still got “it”.

George W Bush achieved the hitherto unimaginable this week when he caused folk to look on him anew as beacon of good sense and restraint. In a interview on NBC’s Today, Dubya, asked about the tension between Donald Trump and the media, described a free press as “indispensable to democracy” and said the country needed answers on the new administration’s links with Russia. Wield the air freshener on that, Donald.

But Mr Bush is but a novice compared to John Major. The former Conservative prime minister, who once called the parentage of three of his Cabinet ministers into question, likes to ration his public interventions, presumably to avoid too many asterisk-laden accusations coming back at him.

As it is, his speech on Monday at Chatham House in London caused former colleagues to call him “bitter” (Iain Duncan Smith) and “yesterday’s man with yesterday’s opinions” (Jacob Rees-Mogg). It was left to Nadine Dorries to truly stick two fish fingers up at the former premier, calling him a “dull, irrelevant, sad, adulterous, hypocritical, pompous has-been”.

What had Mr Major said to cause such ire? The subject was, of course, Brexit, a topic that makes the Scottish independence referendum look amateurish in its ability to start a fight in an empty house. Calling the EU referendum last June “one of the most divisive votes in British history”, Mr Major said a hard Brexit, in which the UK quits the EU single market lock, stock and barrel, would encourage another Scottish independence referendum.

If Scotland was to become independent, he said, “both she and the UK would be diminished”. Promising to return to the matter of Scotland and Northern Ireland on another occasion, he turned his attention to Downing Street and Leavers in general. And boy, did he turn on them.

Yes, he said, the EU was not perfect and it was true the economy had not gone belly-up since the Brexit vote. But the country has not yet left the EU, he reminded the audience, and he is worried that people are being led to expect a future that seems “unreal and over-optimistic”. Moreover, he had found the post-referendum debate “deeply dispiriting”. It should be acceptable to speak out without the risk of being called unpatriotic, elitist, or out to undermine the will of the people, he said.

Finally, in words that appeared to be aimed directly at Downing Street, he called for an end to the “sour atmosphere” around EU negotiations and said “a little more charm and a lot less cheap rhetoric” would do far more to protect the UK’s interests. Cheap rhetoric? Sprinkle the Shake n’ Vac over that one, Theresa.

As with Dubya’s comments on Donald Trump, Mr Major’s Brexit intervention (followed yesterday by similar warnings from former chancellor George Osborne) casts him in a new, more flattering light; not to everyone, as we have seen. But among those who feel the Brexit debate could do with far less heat and a lot more light, the words of Mr Major will be greeted warmly. Although there is a long haul ahead on Brexit, today is a key date in the calendar, marking as it does the start of a very important month. All being well according to Mrs May’s plan, the Article 50 Bill will be law by the early part of next week.

That gives her three weeks to trigger Brexit by her self-imposed deadline of the end of March. That, in turn, affords Nicola Sturgeon the chance to call a second Scottish independence referendum at the SNP Spring conference over March 17 and 18. Downing Street is ready for this, we are told. In the same way, barely a day goes by without reports that the First Minister is preparing to name the day.

One would say the drums of political war are growing louder, but that does not suit the style of either leader. The mood music is definitely changing, and not always for the better. Both women have good reason to do as Mr Major advises and turn down the volume on expectations and, in Ms Sturgeon’s case (because Mrs May would rather cartwheel along Downing Street than say something headline-grabbing), tone down the rhetoric.

If Ms Sturgeon was to ever give up the politics lark and become a former leader herself, she could do worse than turn to novel writing, for she has proved to be endlessly inventive in reworking a formula to successful effect. When it comes to hinting that a second referendum is on its way she could put JK Rowling to shame. Even here, however, one senses the First Minister is becoming bolder with her narrative, as when she accused the UK Government yesterday of adopting an “its-way-or-no-way” approach in Brexit talks, and said that “if” a second referendum was called it would not be down to bad faith on her part but to “sheer intransigence” on Mrs May’s. That sounds like real, referendum-fighting talk.

If both leaders are to take anything from Mr Major’s Chatham House address it is, to use a phrase the boy from Brixton never would, that there is a lot to be said for cawing canny, on Brexit and much else. For now, the pressure is on Ms Sturgeon to make a decisive move, even though the polling numbers should be advising her otherwise. But in time, when Mrs May’s honeymoon is over (and it will end at some point, regardless of Jeremy Corbyn’s heroic efforts), she too will come under pressure to take momentous action just to satisfy the increasingly strident calls of those around her. Mr Major will not be the last politician in history to come across bastards only too keen to grind him down.

There is another reason to heed if not the words of Mr Major then the example he set. His often torrid time as prime minister was a lesson in what happens when a single issue is allowed to consume first a party, then a government, and finally a premiership. Ms Sturgeon and Ms May may tell themselves they can handle the question of Europe better than Mr Major ever did. Perhaps they can. But he thought the same about his predecessor. Look how that turned out.