THE former PM Jim Callaghan once said that there are times in politics when a sea-change happens and it doesn’t matter what politicians say or do: the change is coming. It happened with Thatcher. It happened with Blair. It happened with Scottish devolution. But it hasn’t happened yet with independence and Nicola Sturgeon – in public, finally – seems to have accepted it.

The First Minister’s acceptance did not come easily though. In a slightly awkward speech on the day Britain left the EU, Ms Sturgeon said she and her party had to be realistic and recognise independence would not come without a broadening of the coalition supporting it. However, she also had the cheek to say there were no shortcuts to another referendum, having spent the last few months suggesting there might be. And she said she would continue to do all she could to secure a referendum this year. Is there anyone left who believes that?

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For many nationalists, the speech was infuriating – Wings Over Scotland called it a betrayal – but for many unionists and centrists, I suspect Ms Sturgeon’s words will have come as something of a relief. Yes, she said the party would be ramping up their independence campaign and taking out newspaper ads and all the rest of it, but more significant was the tone. There won’t be a referendum this year, there was never a chance of one, and there won’t be another until there is broader support. It was this more realistic slant – however reluctantly it’s been dragged out of the First Minister – that will have felt like a welcome change for many voters.

I’m not saying something radical has happened here – today, we are broadly where we were yesterday – but perhaps Ms Sturgeon is starting to accept in public what she may have accepted in private for some time. I have no doubt – even though it would be outrageous – that the SNP would say a 50.00001% vote for Yes would be a win, but political history shows that big change tends to come only with a big consensus. It makes the change inevitable, in the way that Jim Callaghan recognised, but it also lasts because it’s accepted.

This is what the history of devolution teaches us. In many ways, the campaign for a Scottish Parliament was built on a negative – opposition to the Tories – and some of this also drives the campaign for independence. But the difference between then and now is that Labour backed devolution. There was also wide support across all social classes, although support for devolution was higher (as is support for independence) among men, the working class and the young. Even the business community, although it was worried about the tax-raising powers, said it could accept a Scottish parliament.

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What all of this led to was a referendum in 1997 that was a foregone conclusion. The sea-change had happened and the referendum merely confirmed it, with 74.3% backing a parliament and 63.5% voting for tax-raising powers. Key parts of society, across all classes, cultures and parties, had been won over. A consensus had been built and that’s why the referendum happened and that’s why the result was accepted.

In her speech, Nicola Sturgeon seemed to be acknowledging that she needs to build the same kind of consensus on independence, and if she was, she’s right; her hopes of building it also seemed to be zeroing in on one group of voters. “There are many people who voted No in 2014 now thinking about independence differently in light of Brexit,” she said. “We must show that we understand the complexity of the issues they grapple with and that for many, emotions will be mixed … and make our case with passion but also with patience and respect.”

Ms Sturgeon is right to focus on these voters, for they are surely the key to the fate of independence and the First Minister. For a start, what she says about Brexit is true: many of those who voted No in 2014 do seem to be changing their minds because of Brexit. Last week’s YouGov poll found 21% of those who voted Remain in 2016 and No in 2014 said they would now vote Yes to independence. Given the YouGov poll estimates 29% of voters fall into the category of backing No in 2014 and Remain in 2016, and given that 2.5million voted in the EU referendum and 3.5million in the independence referendum, I think a fair estimate of the number of No-voting Remainers who’ve switched to Yes would be 200,000. It’s a lot of voters with a lot on their minds.

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The critical question is how the views of these voters will develop, and whether the group will grow, and that depends on the economic impact of Brexit. If the economy does OK after Brexit, will some Remainers start to feel less inclined to want out of the UK? Other voters may say “well, if the economy is OK after Brexit, perhaps it will be OK after independence too.” Alternatively, if the economy suffers under Brexit, that might incline voters against independence on the basis that, if a Brexit break-up is bad for the economy, a Scexit break-up would be even worse.

None of this is easy to predict but what we do know is that the economy is uppermost in many voters’ minds when there’s talk of breaking up a union and so it will have to be central to the First Minister’s efforts to build a consensus. She will need a lot of other things to fall into place – support from Labour, or at least a lot of Labour, more support from business, and more support from women and the well-off. But she will also need voters to take a look at the economic impact of Brexit and conclude that independence would be OK, or at least not as bad as all that.

My judgment is that she’s still a long way from that point. I remember what the 90s were like: if you didn’t support a Scottish Parliament, you were a bit of a freak; there was a consensus; there was one of Jim Callaghan’s sea-changes. But that is not where we are in 2020. There is no consensus. We are divided. There may be strong tidal currents, and there may be a flow towards Yes. But that, as the First Minister finally appears to be recognising, is not quite the same thing as a sea-change.