IT’S the party’s reason for existence, its uniting force, the prime motivator for members and the cause for which it won far more support than expected in a historic vote less than 18 months ago.
Yet some in the SNP seem to believe independence should not feature in the manifesto for the Holyrood elections, now just 99 days away.
Pete Wishart, one of the SNP’s most senior MPs and chair of the Commons Scottish Affairs Committee, says he is “relatively relaxed” about whether or not the party offers voters a commitment to hold another independence referendum.
“This election will be about stewardship of public services and whether people have confidence in the SNP,” says Mr Wishart. “We’ve had that referendum, we got a decisive result, and we said that would be a once-in-a-generation referendum. Unless something significant and substantial happens in the next few years, I think that’s something that we have to respect and observe.”
His comments – which echo sentiments often voiced by the opposition parties – will cause many raised eyebrows.
He is right that voters going to the polls on May 5 are choosing who should run Scotland for the next five years and should make up their minds on the party’s competing programmes and personalities.
Perhaps Mr Wishart believes the electorate at large resents the continued debate about Scotland’s constitutional future. But if that is the case, there is little evidence that it is damaging the SNP’s poll ratings.
The SNP has always included independence in its manifestos and it can be pretty confident including it again is not going to stop it being re-elected in May.
Nicola Sturgeon has, of course, made clear she does not plan another referendum until she is confident she can win it. Privately, it is said she would want to see Yes support at 60 per cent for a year before risking another vote.
The other potential trigger for a second independence referendum would be if Scotland votes to stay in the EU while the overall UK result is to leave – which could happen.
But without something in the manifesto to allow for the possibility of calling a fresh vote, Ms Sturgeon will be stymied. She needs to be able to show she has a mandate for a second referendum if she decides it is appropriate.
The Edinburgh Agreement, signed by the UK and Scottish governments, smoothed the way for the 2014 referendum.
But David Cameron has already indicated he is not keen to sign up for a second. With no SNP mandate to hold a new referendum, he can simply refuse. With a mandate, he may well still try to block a fresh vote but would find it harder to succeed.
It could be argued the SNP’s victories in the Holyrood elections of 2007 and 2011 were won by sidelining the issue of independence with the promise of a referendum, thus allowing people to vote SNP without having to sign up for a separate Scotland.
And the party continues to attract support from people who do not necessarily want independence.
But the referendum campaign and its aftermath seem to have produced an unprecedented surge in support for going it alone. It is not yet a majority – and it may not become one.
But whatever one’s views on the issue, it would surely be an extraordinary situation if Scotland’s party of independence, at the very height of its popularity, went into an election having abandoned mention of its number one core belief.