A couple of weeks ago, I attended an “in conversation” event with the American sociologist Arlie Russell Hochschild at Harvard University.

She was talking about a new edition of her book, “Strangers in Their Own Land: Anger and Mourning on the American Right”, an account of her five-year immersion with Tea Party supporters in Louisiana.

In the course of her research, Hochschild hit upon a paradox, that of voters in a poor Southern state voting for candidates who scorned the federal government, its programmes and funding – voting, in other words, against their own interests.

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This paradox could only be explained via Hochschild’s concept of the “deep story”, from which moral precepts and “facts” were drawn by the Tea Party supporters she studied, whether or not they were empirically true. It reflected a keen sense of decline, of having been left behind, becoming “strangers” in their own land.

While Hochschild was writing about a political movement in the Deep South, her perceptive analysis could be applied to much of modern politics on both sides of the Atlantic. The Tea Party movement now looks like a proto-Trumpian phenomenon, while in the UK large votes for independence and Brexit also drew upon “deep” stories of their own.

The Scottish version runs deeper than most. For most of my adult life, a section of the Scottish political classes – at first Labour, and then the SNP – told an endlessly-cultivated story of Scotland as a uniquely “progressive” and “social democratic” nation which occupied the moral high ground in its approach to both international and domestic affairs. And, since the 1980s, it was depicted as being under constant “threat” from an “alien” story propagated by southern Conservatives.

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It didn’t really matter that this story was more rhetorical than real, for it “felt” salient and true; indeed, I still encounter Labour voters who have remained loyal to their party while essentially sharing the same “deep story” with their Nationalist enemies. Much of the past 40 years can be understood as a competition between Labour and the SNP for control of that narrative.

A few days ago, it was even beamed back at me in a small Manhattan cinema. “Scotland is Now” featured the usual rolling landscapes and tartan parades, but also the nation’s claim to be “innovative”, welcoming and, of course, “progressive”. It was, of course, intended to inform the audience’s vacation planning, but in doing so it subconsciously sought to contrast Nicola Sturgeon’s Scotland with that of Donald Trump’s United States.

The SNP has its own deep story, one in which it keeps its promises, never compromising, spinning or fudging as Tories and Labourites are inclined to do, thus the party’s recent indignation at being caught out over the Cambridge Analytica affair. They associate that sort of hypocrisy (and, it has to be said, poor internal communications) with their opponents, thus the First Minister protested that she’d been completely transparent when it was palpably obvious she and her party had been nothing of the sort.

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And now we’re more than half way to leaving the European Union, the central elements of another “deep story” are also clear. The Brexiter version views England/Britain/UK as a blessed isle, a nation endowed with a sense of fair play and buccaneering spirit both at home and abroad. It’s a story that hasn’t entirely come to terms with the loss of Empire, but one that believes its new role ought to lie outwith the European Union.

Once again, this “deep story” is impervious to facts, firmly believing the UK will soon triumph economically via mystical new trade deals in spite of overwhelming evidence to the contrary. The 2016 European referendum was essentially a clash between that view of the world and yet another deep story, that of a liberal nation at ease with itself and whose destiny involves working alongside the historic nations of Europe.

In discussing her book, Hochschild took care to concede that (American) liberals had their own “deep story”, although those in the overwhelmingly white, upper-middle-class and academic audience didn’t seem in any mood to acknowledge that. Several questioners referred to “these people”, by which they meant Tea Party supporters in Louisiana, and what could be done to combat them so their preferred story could get back on track.

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It was a reminder that deep political stories exist across the ideological spectrum, but what links them all is their salience. Take the Corbynista view of the UK, a long-standing Left critique that Britain and the West are uniquely wicked and not to be trusted even when it comes either to domestic poisonings or foreign chemical attacks. And once a particular group of voters discovers someone who articulates their narrative, he or she can do no wrong. “I’d spent five years with the dry kindling,” Hochschild recalled of attending a Trump rally with her subjects in 2016, “then I saw the match.”

In that sense, contemporary politics has little to do with policy and everything to do with identity, for all these competing stories speak to each political tribe’s view of who they are and what they stand for in an increasingly complex – and therefore frustrating – world. At the same time, it’ll be interesting to see if those narratives can survive ongoing clashes with reality. Salience, after all, can diminish over time.

I guess a lot of my columns in this newspaper have probed various “deep stories” – be they Nationalist, liberal or Brexiteer – since my first appeared in late 2013. Sadly, this is my last, but over the last four and a half years I hope I’ve succeeded in describing Scottish politics as it is rather than how I or others would like it to be. It has, of course, been a privilege.