If you were looking for a metaphor on what four decades of the relentless drive for introversion have done to Scottish politics, it would be worth considering two trade-related stories which featured over the past few days.

The first recalled a noble episode in the 1970s when the trade unions at Rolls Royce in East Kilbride blocked the removal of refurbished engines bound for the military junta which had seized power in Chile, overthrowing the elected government of Salvador Allende.

The Hawker Hunter aircraft for which the engines were required were the same ones that bombed the Presidential palace as Pinochet seized power. This week saw the premiere of a documentary film, Nae Pasaran, which recalled not only the principled stand of the Rolls Royce workers but also the impact it had within Chile.

A Walker's shortbread tin decorated with a Union Jack caused uproar among some nationalists

Fast forward to 2018 and what great issue of trade is making the headlines? Is it a stand for peace or principle? Are we sending out a message to some corner of the world about what Scotland, at its best, has to offer? Alas no. Scotland’s most prominent trade dispute of the day involves the packaging of shortbread.

A vigilant surveyor of the biscuits aisle in a German supermarket spotted some Walker’s shortbread tins which featured the Union Jack. Alison Brown, replete with a Yes logo, tweeted: “It breaks my heart. This is how Walkers are marketing our famous Scottish shortbread in Germany! Our hard-won Scottish branding is being systematically destroyed! For what? To protect their Union! I feel so sad and angry.”

Anger over Union Jack flag branding on Scottish shortbread

Anywhere else in the universe, there might have been a strong suspicion that this posting was the work of a satirist, designed to draw the unwary into making fools of themselves by endorsing it. But this is Scotland and the ball was well and truly rolling. A boycott was demanded. Walker’s was inundated with abuse as the shortbread soldiers prepared for an all-out assault on Aberlour.

Minimal inspection of Ms Brown’s online history confirmed that she spends much of her life in a state of outrage over such affronts. Thankfully, by Tuesday, she had emerged from her slough of despond long enough to prompt followers to “vote for Nicola” in order to have her declared “the most influential woman in Britain” in a Sky News poll. The duties of a civic nationalist are many and varied.

Walker’s issued a statement explaining their position and pointing out that they do rather a lot for Scotland, not least of which is to employ 1,700 people between Aberlour and Elgin. Boycotting their products would threaten some of these jobs, the great majority of which depend upon exporting.

At this point, Ruth Davidson tweeted succinctly: “The absolute state of things when Walker’s feel compelled to put out a statement about a commemorative tin.” This modest observation drew a remarkable response from an MSP – yes, I repeat an MSP – by the name of Fulton MacGregor: “That’s the British Nationalist way – ashamed to be Scottish.”

By this time, most satirists would have admitted defeat on the grounds that you couldn’t make it up. Yet it is an episode which epitomises the mood music which now plays constantly in the background of Scottish public discourse. Grievance, bullying and threats to those who offend the prevailing orthodoxy are never far away.

The choice of Walker’s as a target is bizarre. Not only are they one of our greatest exporters, infiltrating even the most unlikely corners of the world, they also do more to promote tartan than any organisation up to and including the Scottish Pipe Band Association. The idea of this thoroughly decent company being assailed by a bunch of small-minded political fanatics should offend us all.

It’s too convenient to brush aside stories like this while exploiting the atmosphere they are intended to create. We have heard a lot of condemnation in the past couple of days of other forms of offensive online behaviour. And quite right too. But politicians should also look at their own back middens and do something about them. Mr MacGregor’s response to Ruth Davidson might be a good place to start.

I do not wish to further distress Ms Brown and her army of the indignant but I suspect the Scottish Government is quietly latching onto the fact that Scotland’s trade and investment strategy, which is in dire need of a boost, is best served by taking advantage of both Scottish and British dimensions. Recent appointments by Scottish Development International have been, sensibly, co-located within British embassies in order to work together rather than in competition.

The truth is that almost every significant Scottish exporter operates in this way. There are some markets and sectors in which the Scottish identity plays well and far more in which Britain is a stronger brand. Who cares? We have the benefit of both. Surely what matters is that Scottish firms are successful in exporting, using all the tools at their disposal, and creating jobs at home.

The problem is that we do not have enough companies exporting while there is too weak a presence in the world’s fastest growing markets, such as China and India. I don’t care what flag is flown to address these issues. Brexit is a challenge as, according to the Scottish Government’s figures, the EU accounts for £12.7 billion of our exports. However, it should be more of a worry that we sell only £17.1bn worth to the rest of the entire world.

Both these figures are dwarfed by the £45.8bn of exports to the rest of the UK, making clear beyond doubt that this is the single market which matters most to the Scottish economy. Maybe the occasional hand of friendship to our biggest market for goods and services would not go wrong, instead of the constant search for division and offence.

I leave the last word to Jim Walker when I interviewed him recently about his company’s success.

“You can’t just slap a bit of tartan on it and expect it to sell … it’s the quality of what’s inside that matters,” he said.

You could say the same thing about people.

Brian Wilson: How Nationalist bullies pose threat to Scottish economy