IN democratic politics, churn is inevitable. The results are not always immediately beneficial but, still, one must refresh the screen from time to time.

John Swinney, I am told, gave some thought to contesting the leadership of the SNP.

Had he done so, he would have won. He would have become First Minister. Which no doubt concentrated the mind somewhat.

And so he concluded, fairly rapidly, that it was time for others to step up. Which meant, inevitably, that he has stepped down.

His would have been too senior, too powerful a presence for the new leader. His logic is impeccable.

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Critics said he was deserting the sinking ship of his party. However, most praised his stoicism and fortitude in office.

Added to which, I would simply recall his good humour and his frequent rhetorical passion, either defending the vulnerable or pursuing independence.

It all adds to the sense of a new direction for the SNP, with a new generation in charge. But in charge of what? Taking the party – and the Scottish Government – where?

It is difficult, in truth, to gauge the nationalist movement from this somewhat strained leadership contest, distorted as it is by the early spat over moral issues.

However, it would appear that a different direction is emerging. In pursuing independence, the object will probably be to focus more on why, rather than how.

To talk of the proclaimed benefits of independence, rather than arguing over whether the next UK General Election might serve as a referendum.

The Herald: Nicola Sturgeon is standing downNicola Sturgeon is standing down

That, in short, de facto is defunct.

In this leadership contest, there is inevitably a dichotomy on display.

The candidates know they need to convince the wider electorate that they are fit to govern as First Minister, that they have plans to address economic and social problems.

However, to gain office, they must initially win the backing of SNP members. More precisely, those members who are active and therefore inclined to take part in the ballot.

By definition, they are likely to be sharply focused upon independence as a desirable solution to Scotland’s problems. They are likely to accord great significance to that issue.

In which regard, this week, we discerned the emergence of a new front, in response to the Windsor Framework for the post-Brexit governance of Northern Ireland.

The deal struck by Rishi Sunak with the EU is designed to allow cross-border trade on the island of Ireland – while simultaneously easing the path from Cairnryan and other mainland GB ports.

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It would be churlish to deny a moment of smiling pride to Mr Sunak. Or “dear Rishi”, as the EU’s Ursula von der Leyen described him.

Churlish, indeed, to recall that it was Mr Sunak’s own Conservative Party which implemented Brexit. Still more churlish to inquire as to the billions of pounds in trade apparently lost since the UK left the EU.

So we will desist. And ask instead where Scotland sits in the new framework. Stephen Flynn, the SNP’s Westminster leader, made his case.

He noted that the Prime Minister had talked up the “exciting” benefits to Northern Ireland of retaining, in effect, links with the European single market.

Why, he inquired sardonically, were those gains being denied to Scotland and the rest of the UK?

This is a familiar argument for nationalists. In December 2016, the Scottish Government published a document, Scotland’s Place in Europe, which examined options as to trade with the EU single market.

You will not be surprised to recall that the “best option” was full, independent Scottish membership of the EU. The others were the UK as a whole or Scotland alone retaining links with the single market.

Be clear what is happening now. The SNP is reviving a familiar policy in response to contemporary developments.

But be clear further. They do not remotely expect the PM to say Yes, to concede single market status to Scotland, even if the EU were at all willing to bargain.

One insider told me “that ship has sailed”. Another was even more blunt. “We are chancing it and we know we are chancing it.”

So what is going on? It is, of course, about independence, rather than about pressure for enhanced powers within the current devolved structure.

It is about demonstrating to the Scottish people that Scotland’s interests are ill-served by the Union. It is about inviting the conclusion that “real change will never come from Westminster”, as Mhairi Black, Mr Flynn’s deputy, put it in a speech to the Plaid Cymru conference.

The SNP has signalled support for the Windsor Framework. Partly, that is authentic backing for the principle, for efforts to secure peace in Northern Ireland.

But it is also partly a calculation that there are political gains to be made for the SNP, particularly while Labour adheres to its determination to avoid contesting Brexit.

In essence, the argument goes that Scotland, alone in the UK, has failed to get what its people wanted in the Brexit referendum.

Both England and Wales backed Brexit. They got it. Northern Ireland voted Remain – and has now got special treatment. Scotland, says the SNP, endorsed Remain by a larger margin – yet has lost out as a consequence.

There is another element in the Windsor deal. Might it change the atmosphere in relations with Brussels? Might it just, perhaps, enable an eventual agreement to the cross-border challenge which would arise if an independent Scotland joined the EU?

That is undoubtedly a stretch. Critics say the Border with non-EU England would present a huge challenge, that Northern Ireland is, as all recognise, a special case.

However, SNP strategists are developing their thoughts. They say they can shrink the scope of the border issue.

For example, they say that what is known as a veterinary agreement, covering regulations on animals, plants and food, could significantly reduce the need for cross-border checks.

They say that an independent Scotland, in the EU, could build upon existing trade with the rest of the world, while also seeking to maintain a Common Travel Area across our islands.

Familiar policies and derided by opponents. But also, perhaps, the kernel of new thinking. For a new SNP leader.