There was a widespread sigh of relief, this week, as Scotland’s Finance Secretary Derek McKay rose at Holyrood to make his annual draft budget statement; not because the statement was a joyous or even particularly interesting one, but because it seemed to represent a brief oasis of ‘normal’ politics, amid the obsessive Brexit chaos now sweeping Westminster.

Among other familiar bread-and-butter issues, there were Tories arguing that taxes on the well-off should be lower, while the SNP suggested that maintaining those tax levels – while Westminster cuts them – is both sensible and right, to protect Scotland’s public services; and in a week that saw Westminster convulsed by one Brexit-related crisis after another, this straightforward budget discussion seemed like an old political colleague not encountered for a while, and greeted in the lobbies of power with a warm handshake. Nicola Sturgeon even said that it should remind people what “strong and stable” government really looks like; although that seemed a little bit of a stretch, for a Scottish Government not yet certain that its budget can even muster a Holyrood majority.

There is no room, though, for any complacency about the state of Scottish politics; and not only because of the growing threat of a chaotic Brexit. For while, at the moment, the focus is on the searing divisions in British politics opened up by the EU referendum of 2016, the fact is that the 2014 independence referendum also left Scotland deeply divided, with two roughly equal bodies of opinion completely unable to agree, in a dispute that encompasses every aspect of our future collective life, from practical economic policy to the deepest questions of identity and belonging.

Derek Mackay and Nicola Sturgeon helped return politics to something like normality this week (Picture: Greg Macvean)

And as if to remind us of those divisions, this week the UK Supreme Court delivered its opinion on the legitimacy of the Scottish Parliament’s Continuity Bill, designed to transfer EU legislation in devolved areas into Scottish law, and overwhelmingly approved by the Scottish Parliament in March of this year, with only the Tories voting against. The Presiding Officer of the Scottish Parliament, Ken McIntosh, had already given his opinion that the bill was beyond the Parliament’s powers; Scotland’s Lord Advocate disagreed. And the UK Government, particularly exercised by a clause which suggested that it should not be able to change the balance of powers on devolved matters without the consent of the Scottish Government, decided to take the whole matter to the Supreme Court, in order to ensure that the writ of its own EU Withdrawal Act – complete with sweeping “Henry VIII” powers – would run across the whole of the UK.

Parts of Scottish Brexit bill ruled to be outside Holyrood's devolved powers

Now it would be possible to elaborate at some length on the wisdom and elegance of the Supreme Court’s judgment, which both confirms the essential legitimacy of Scottish Parliament’s decision to enact a Continuity Bill, and points out one section of the bill in particular, the one involving consent, which is beyond the Parliament’s powers, along with a few other paragraphs which have become so, thanks to a special amendment written into the UK’s EU Withdrawal Act after the Continuity Bill was passed.

What is most striking about this ruling, though, is the extent to which reactions to it immediately became polarised, with the Scottish Conservatives hailing the result as a well-deserved humiliation for the SNP, while the SNP and ‘Yes’ supporters immediately highlighted the Supreme Court’s recognition that Holyrood had the right to legislate in this matter, and that the British Government had changed the relevant UK legislation – “shifted the goalposts” – following the passage of the Bill.

The response, in other words, was dictated – like attitudes to Brexit at Westminster – by a series of visceral emotional decisions about where we belong, and whom we trust. To me, as a “yes” supporter, it seems pretty clear that a British Conservative Government some of whose supporters still think Ireland – after almost a century of independence – should “know its place”, cannot be trusted with the UK’s devolution settlement of 1998; that their treatment of Scottish opinion throughout the Brexit process has been contemptuous at best, and that their high-handed attitude puts our current devolved institutions at some risk.

Yet to a Conservative like Adam Tomkins MSP, the Scottish Tories’ constitutional spokesman, it seems equally clear that the SNP are just nasty schemers trying to break up the British state by underhand means, and that the Westminster Government are true-blue trusty sorts who, if they do remove powers from Holyrood, will only be doing it for our own good. He described the Supreme Court’s decision as “eviscerating” the Scottish Government’s bill, rejoiced that it had been “left in tatters”, and declared that Holyrood should simply bin it.

And the question that lingers, of course, is how any nation finally moves on from this kind of emotional deadlock. If we look across the sea to Ireland, we see a country that would not now dream of giving up its independence, even though it had to sacrifice a large dissident chunk of its territory to get it, and was so divided on competing visions of it that a bloody civil war ensued; but only time will tell, this time round, whether it is my gut feeling, or Adam Tomkins’s, that is on the right side of history. The common wisdom of Europe, after 1945, was to argue that it never pays, at least on our continent, to indulge in the politics of national identity; and that unity and compromise is always better than separation.

That settlement, though, depended on two things; on the implementation of enlightened postwar economic policies aimed at winning popular consent through full employment and mass prosperity, and on a dominant set of liberal values which allowed full expression and recognition of powerful national and regional identities within existing states. And once a state like the UK falls into the hands of a party and government which accepts neither of those preconditions, all bets are off; which is why the current spectacle at Westminster, increasingly driven by Conservative pro-Brexit extremists, is of such crucial importance to our future, and to the powers and resources future Scottish finance ministers will have to hand, when and if they rise to present their annual budgets for 2020, 2030, and all the years beyond.

Why Tories can't be trusted with devolution '“ Joyce McMillan