NICOLA Sturgeon’s big announcement has proven a major watershed; an act of leadership, boldness and clarity which has surprised her opponents and many on the independence side.

Her referral of an indyref to the UK Supreme Court goes to the heart of where power and legitimacy sit, the nature of democracy, and the reality of the UK and Scotland’s position within it.

Make no mistake, this throws up big challenges for independence. For getting serious about how politics is done, the substance and detail of independence, and of people not getting trapped in their own echo chambers.

Independence supporters need to focus not just on their own passions but on how they listen and win over the Scotland still sceptical, doubtful and unpersuaded who come in all shapes and types. Too many independence supporters miss this basic fact.

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The challenges facing the pro-Union side are as great. They have no strategic offer and have a set of problems about the nature of the UK which go way beyond Boris Johnson.

For one thing they are stuck talking about “process” – how a referendum can be called – which as John Curtice points out makes their defence very narrow and once, as it will, it is evacuated they will be on very dangerous and weak territory.

While independence supporters need to think about how they present their case and do politics, the fundamental issues of Scotland’s position and right to self-determination and the nature of the UK has now been placed centrestage.

The UK is a union, a union of consent, but if the Supreme Court rules that Scotland cannot decide on its own to have an indyref, the nature of that union is irrevocably changed to the detriment of the Union.

This is a point that Ciaran Martin, the lead negotiator for the UK Government in the 2014 vote, has repeatedly made. The UK Government continually refusing Scotland’s right to decide its future brings forth the fundamental question, according to Martin, of “is this a voluntary union and union of consent” or not?

Sturgeon’s position is as Martin has said to “force the UK Government out into the open”.

But it is also about a bunkerist Unionism finding increasing voice, not just in deep cyberspace, but amongst prominent supporters.

Tory grandee Malcolm Rifkind referred this week to “little Scotland, my country of birth, in a very, very lonely place”, trying to paint an isolationist independent Scotland, outside the UK and EU.

And there is the Bruges Group of Thatcherite Tory Brexiteers confidently declaring “The UK is not a union, it is a country – whole and entire”. Maybe someone should tell them the full name of the Tories - the Conservative and Unionist Party – and that you cannot have any Unionism without a Union to defend.

Similar tones have been heard from Alister Jack, Secretary of State for Scotland – a post which used to carry prestige and was held by big hitters. Jack objects to the description of the UK as “the four nations” thinking it carries some kind of dangerous equivalence between the four and the UK.

If people want genuine loopiness there is always GB News. Step forward broadcaster Colin Brazier marking the 15th anniversary of Tony Blair’s departure as Prime Minister on Monday. He regaled us with his list of what he deemed were Blair’s four biggest failures in office, the first of which was devolution.

Brazier said that devolution “wasn’t a brake, it was an accelerator” of the break-up of the UK and went on: “Nobody has done more to break up the most successful political union in history than Tony Blair. In another age he would have been fined for treason.” Why stop at fining? Such moderation!

WE are going to hear a lot more of this talk in the coming two years. It isn’t a good sign about the pro-Union argument. We will hear endless mantras about “divisive referendums pitting family members against family members” when that is an argument taken to its logical conclusion against democracy and elections.

All this means that independence has to rise to this occasion. There can be no listening to, and tolerance of, the small group of over-zealous folk on the fringes. There can be no time given to haters, bigots and abusers. And there can be no indulgence of over-the-top fantasies such as the video produced by Now Scotland called “Summer Of Disobedience”.

There is a legitimate case for the Union. It may be getting weaker by the day. It may not have a strategic offer to remake the UK on economic, social, democratic and geopolitical terms. Too many independence supporters do not think there is any rational case left for the Union – which means they do not understand, or in some cases respect, the many reasons a large number of Scots have for not supporting independence and believing in the Union.

In my forthcoming book Scotland Rising: The Case For Independence, published later this year, I outline the argument for independence but also the argument that is put forward to defend the Union.

A better, more confident, mature independence would be prepared to recognise that there is a case for the Union which is not about brainwashing, propaganda, control from London or the Stockholm Syndrome with Scotland being held in the Union against its will.

Independence has not only to challenge the broken economic model, the atrophied democracy and corrupt politics of the UK and break from the increasingly isolated pariah that the UK is on the international stage. It cannot just be about independence as an abstract, or peddling a “little Britain” version of change where the only thing that changes is the order of flags on public buildings.

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Everything has to be geared towards independence embodying pluralism, tolerance, listening – and as Mike Small of Bella Caledonia said, even “softness” – because, in this age of noise, softness can have impressive power.

We have to break out of the usual suspects and as Small says have “less men” making the case and more diverse voices. Not only is this not just about the SNP, but the SNP leadership have to be more generous and inclusive in their politics and learn that a politics of sharing, co-operation and different perspectives can be a symbol of strength not weakness.

Every public independence stance should be geared not towards making people feel good or affirming their own priorities. Rather the focus has to be on the Scotland to be won and hearing, respecting and accepting different views. This is no time for indulgencies, flights of fantasy, conspiracies and other diversions.

That does not mean giving Nicola Sturgeon or the SNP a free pass. It demands that each and every independence supporter acts as an advocate for the future Scotland we want to bring into being.