The SNP won’t hold a second independence referendum until it knows it can win. That is an obvious statement, but it seems to have been missed by the party’s opponents. They should be pushing SNP leader Nicola Sturgeon to admit that, for the first time in its history, the party could go into two successive elections without prioritising independence or pushing for a referendum. Instead, they are looking for a way to say that the SNP will jump at the first opportunity. What nonsense.

Sturgeon’s line is that it would take a material change for the SNP to push for a referendum in the near future. One change is obvious: if there is a referendum on the EU and the UK votes to leave but Scotland votes to stay, it will prompt a constitutional crisis and a likely second Scottish vote.

The other is not obvious: if there is a surge in support for the SNP or for a Yes vote in the opinion polls. The surge in SNP membership, to more than 100,000, is significant for them, but not for the vote. It was likely to have been caused by disaffected Yes voters able to join easily – online, for a small fee. It does not signal a shift in public mood.

A rise in opinion poll support will be viewed by the SNP as positive but not a clincher, since the ultimate opinion poll took place six months ago, producing a decisive No. One or two post-indy polls are not enough to suggest that the result would change next time.

Playing the long game

Instead, the SNP has to continue to do what it is remarkably good at: biding its time and remaining popular until a longer-term opportunity arises. For me, the magic figure is at least ten years between referendums, for several reasons: to ward off the idea of a “neverendum”, to give people time to become enthused again about a lengthy debate and to find out what people think of the final Scottish devolution “settlement” – which won’t bed in for a few years.

Not to mention that the Yes campaign will need, to put it rather euphemistically, to produce a new cohort of voters to address the fact that older people were far more likely to vote No.

In the meantime, the SNP will try to do two things. First, it needs to demonstrate its relevance on the UK stage, to show for example that it can influence UK decisions regularly – and that only a vote for the SNP will ensure UK government concessions on further devolution in key areas such as social security (although “fiscal autonomy” and “devo max” are non-starters).

Second, it needs to keep winning Scottish parliamentary elections on the back of its strong image of competence in government. Don’t forget that this image, rather than a surge of support for independence, explains its landslide victory in 2011.

The same goes for 2015 and beyond. The SNP won’t win enough votes if it looks like the independence party and nothing more – and it has dealt with that problem well. Its long-term referendum chances hinge on it remaining a credible party of government in Scotland and, for now, a positive force in the UK.