“Brexit is done” – to use Boris Johnson’s 2019 election-winning phrase. But the Conservative prime minister, having successfully delivered Britain’s controversial exit from the European Union, may in future have to deal with the break-up of the United Kingdom.

 On January 28, less than a month since new trade rules and regulations governing UK-EU arrangements came into force, Johnson visited Scotland. Downing Street briefed journalists that the purpose of his trip was to see how the billions of pounds his government has poured into the fight against the covid pandemic is being spent. He went to an army-run covid test centre and then a vaccine distribution hub in Glasgow.

 The obvious message was that Westminster and Whitehall really cared about the crisis “north of the border,” as the English say. Scottish Nationalist Party politicians, however, protested that the prime minister’s visit violated the national lockdown restrictions that he has belatedly imposed across the UK to cope with the highest death rate in Europe and one of the highest in the world. It was an unnecessary journey, they complained (perhaps tongue in cheek), and risked spreading the virus.

 Johnson is rightly concerned by the growing support for Scottish independence.  Nicola Sturgeon, Scotland’s first minister and SNP leader, is perceived to have performed better than he has in tackling covid. And Sturgeon is certainly more popular. In the last referendum, in 2014, 55% of Scottish voters opted to remain in the UK. Signs are multiplying that that is now changing – implying the reversal of the “Act of Union” of 1707 – a landmark in the history of England, Scotland, and the very idea of a United Kingdom. Another official explanation was that Johnson’s trip was “a rescue mission to save the UK.”

 Scotland’s 5.5 million people are more inclined to see themselves as Europeans than their fellow Brits: in the fateful Brexit referendum of June 2016 62% of them voted to remain (compared to 48%-52% across the UK). Staying in the EU was also a key pledge of the pro-unionist camp in the 2014 independence vote.

 According to one recent poll, 58% of Scottish voters now favor independence, meaning the SNP are expected to win a comfortable majority in May elections to Holyrood, Scotland’s devolved parliament. Whether Johnson will then agree to hold another referendum on Scottish independence – as he is legally and constitutionally required to do – remains an unanswered question. But it seems highly unlikely. The prime minister faces no pressure from within his own party – as his predecessor David Cameron did on EU membership – to hold another vote.

 Still, last week came an alarming warning about the costs of Scotland breaking away from the rest of the UK.  An in-depth study by experts at the London School of Economics provided stark evidence that the SNP’s position about post-independence prosperity was misguided: in the big picture, the country’s economy would shrink by at least £11bn a year if it became independent, more than doubling the impact of Brexit.

 The report found that quitting the UK’s common market would hit the Scottish economy two to three times as hard as leaving the EU, just counting the impact on trade alone. And while it would be slightly better for an independent Scotland to re-join the EU compared with staying outside both it and the UK, it would be extremely hard for EU trade to make up for all the substantial losses in UK trade. The UK is Scotland’s largest and most important trading partner, accounting for 61% of its exports and 67% of its imports – around four times greater than its trade with the EU. Independence would increase trading costs with the rest of the UK by 15% to 30%.

 Annoyed by the LSE report, the SNP’s economic spokeswoman insisted that an independent Scotland, like Ireland, Denmark and Norway, would prosper in the long term. That assumption, however, ignores the central question of what currency the country would use – the Euro or remain in a single unit with the UK pound sterling. Either option would require painful public spending cuts or tax rises.

 It does seem that the pursuit of Scottish independence is the equivalent of Johnson’s Brexit strategy – “seizing back control” from Brussels/London – but still being economically damaging. In other words focusing on “national sovereignty” in a globally (and regionally) inter-connected world is an act of self-harm.

 Johnson’s panicky trip to Scotland was a response to criticism that far more needs to be done by his government to prevent the break-up of the UK. In the words of one Scotsman newspaper columnist: “It’s not so much that the case for Scottish independence is being won in Edinburgh, as that the case for the Union is being lost in London.”

 Scottish supporters of independence seem remarkably unconcerned by the potentially disastrous economic consequences. As Matt Ritchie of the northern city of Inverness, put it in a recent letter to the Guardian newspaper: “I have changed my mind on independence. It will be difficult but worth it – worth it to be rid of Westminster. Let Scotland decide.”

IAN BLACK