The fundamental flaw which poses a permanent challenge for Unionist leaders in Scotland

Obliged firstly to endorse Eastasia and then, when the wind changes, to switch his admiration to Eurasia, utterly disowning his previous loyalty.

All because his UK leader, Liz Truss, shifted her stance on the top rate of income tax.

Mr Ross must have gazed helplessly at her works – and despaired.

There she was on the stage in Birmingham. Her tone cod-defiant, then wheedling. Her demeanour like Akela calling a Cub pack to order, all earnest and apprehensive.

The outcome for D. Ross? Personal ridicule and opinion polls suggesting his party faces annihilation in Scotland.

You may tell me he deserves it. Yes, he urged Scotland to mirror the Chancellor’s hasty package.

Then he U-turned in tandem with the PM when she abandoned the plan to scrap the top rate; a clumsy exercise in synchronised swimming.

But consider. This was not an isolated incident. Nor even confined to the Tories. This is a factor of devolved power, a fundamental flaw for the parties who endorse the Union.

That factor has grown in potency over the years as people in Scotland increasingly looked for candidates who would stand up primarily for Scottish interests. For Scottish identity.

It was that identity factor which brought the SNP into being. That same factor obliged Labour and the Liberal Democrats to respond with their plan for a Scottish Parliament.

And that same tendency all but obliterated the Scottish Tories. Ironically, they were saved by the creation of a devolved Parliament and PR elections; two policies they had vigorously opposed.

As Scottish interests came to the fore, rather than Union or, earlier, Imperial concerns, then politicians seeking votes in Scotland were obliged to put a kilt on their offer. Sometimes literally.

But today that leaves them with a dilemma. They project a Scottish dimension to appeal to voters in Scotland. But, always, they have to look over their shoulders to cope with their party’s UK pitch.

Frankly, sometimes there is a clash. Hence Douglas Ross ends up endorsing a tax package which does not even apply, for the most part, in Scotland.

He does so in the interests of wider GB party unity. He does so because he would face contumely and challenge were he to diverge sharply, especially on an issue like tax which is shared between the Westminster and Holyrood Parliaments.

His fellow Unionist leaders have faced similar challenges and may do so again.

Most strikingly, the Liberal Democrats lost ground in Scotland when the party at Westminster entered coalition with the Tories in 2010 – and then meekly accepted tuition fees for university students.

The policy did not even apply in Scotland – in the absence of sun-melted rocks. But Scottish voters knew that the LibDems had formally pledged to oppose tuition fees, and then given in. They exacted revenge.

Scottish Labour too has been shoulder glancing. The party declined in Scotland, partly through laziness and complacency but partly because voters can count.

They knew that a bitterly divided UK Labour Party looked remote from Westminster power.

There have been other examples. In the early days of devolution, Labour and the LibDems implemented free personal care.

But UK Labour Ministers insisted on withholding payments for attendance allowance as a consequence. Scottish Labour leaders privately regret that they did not pick a fight, standing up solely for the Scottish interest. They stood back, to preserve GB party unity.

More broadly, Scottish Labour endeavours can be undermined by conflicts at the Westminster level. Between Blair and Brown, between Corbyn and much of the party.

However, be clear about another point. This flaw, though fundamental, is not necessarily fatal. It can be sorted.

Right now, Anas Sarwar hopes that his GB counterpart Sir Keir Starmer will find the boldness to sustain Labour’s poll lead, largely courtesy of Johnson and Truss.

Mr Sarwar hopes that he can persuade voters in Scotland to return to Labour, tempted by the promise that they will replace the Tories in the UK Government.

By contrast, Nicola Sturgeon has to revert to that fundamental flaw. She has to argue that Scotland needs more than just a new UK Government which can, in time, be changed once more.

Scotland, Ms Sturgeon says, needs a new UK governance in the shape of Scottish independence.

She made that case this week, lampooning Douglas Ross. The Scottish Tories, she said, “just do anything the UK Tories ask them to do”.

By contrast, she pledged to act “in the interests of the Scottish people.” In a news release, her party then challenged Labour to diverge from UK policy on issues like Brexit.

Therein, that fundamental issue. Labour – and indeed the other parties of the Union – must argue that Scotland’s interests can be made coterminous with those of England and can indeed be enhanced by such a merger.

That is the underlying conflict in Scottish politics. Not just between political parties but between systems of governance.

Not much comfort at the moment, I surmise, for Douglas Ross.

In a wireless interview for BBC Scotland, he acknowledged that there was a degree of disquiet about his leadership of the Scottish Conservatives.

In a slightly weary tone, he suggested that those who were muttering about him behind his back might care to emerge into the light. He was, he said, ready for them and confident of surviving.

Two gentle caveats. One, not sure that the plot which ousted Jackson Carlaw was entirely in the open. Quite the contrary, in fact. The eventual beneficiary was one Douglas Ross.

Still, these things. To the second point. Douglas Ross faces an iterative challenge from ideological decisions yet to be taken by his UK governing chums.

Most notably on welfare and whether to peg benefits below the level of price inflation. Wisely, he declined to enter that debate, noting only that difficult decisions were pending but that it was vital to protect the most vulnerable.

It would seem he has learned a lesson. Still, however, a fundamental problem.

Read more by Brian Taylor:

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