MANY SNP members I talk to privately fear their party is about to embark on the same path Labour in Scotland has followed since devolution, electing a series of short lived leaders who fail to halt the decline.

With Nicola Sturgeon’s departure and the collapse in membership figures others worry the best days of the SNP may be behind them. I am not a member of the SNP but I do have an interest in arresting the existing loss of momentum the independence movement as a whole has endured since 2014.  Looking back I believe the movement began to lose its way when it largely dissolved into a single party.

The decision by 100,000 Yes supporters to join the SNP after the 2014 referendum left a powerful cause at the mercy of one party’s whims. And, as Oscar Wilde famously put it, the SNP, despite knowing this was likely to be a backward step, "could resist anything but temptation".  

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Nicola Sturgeon took over as First Minister at the same time and the cult of "Nicolamania" was born. In the world of personality politics she was the queen, no questions asked. 

Accountability, collaboration and collective thinking consequently went out the window. That was not a good thing. Those outside the SNP who warned this was a retrograde step were ostracised. Our voices barely tolerated, our warnings unwelcome. Gone was the collegiate atmosphere of Yes. Nicola knew best and nothing could be allowed to cut across the SNP’s electoral prospects, even when it was clearly to the detriment of the wider independence cause. 

I warned many times over the past 10 years, including in the pages of this newspaper, "it’s not unity the Independence movement needs most of all, it's clarity". But the warnings were not heeded and that clarification has just not been forthcoming.  Unfortunately our movement has stagnated. Support for Independence never secured a majority and now Sturgeon herself "has had enough". 

Felled by her failures like relegating Independence to some adjunct of EU membership, a ludicrous sojourn to the UK Supreme Court and the economic incoherence of her Sustainable Growth Commission were each displays of her "mis-leadership".

And her "mediocre" [Kate Forbes’ description] record in government on health, education, justice, public housing and inequality means history will regard her good at winning elections, poor at delivering material changes.

Politics is unforgiving. The new SNP leader therefore faces the same questions Nicola Sturgeon shirked. How are we ever going to secure majority support for independence? Where is the coherent economic case capable of persuading people of its material benefits? And how, given the intransigence of the British State are we to achieve it democratically?

To be fair, I never heard any of the three SNP leadership candidates answer these questions adequately.

The fact remains the SNP cannot achieve independence on its own. No one political party can. They need the help only that wider movement can provide. The new SNP leader must therefore allow other voices to be heard if this is to genuinely become a mature, democratic movement.

It’s more than 10 years since I was invited to join Yes Scotland as a Board member. I represented the Scottish Socialist Party on the Scottish Independence Convention for a decade before that. All of which leads me to suggest it is time for the Independence movement as a whole to come together again and establish a collective, single body with the ultimate responsibility for taking our movement forward and delivering our shared goal.

The National: Humza Yousaf faces the same questions as his predecessorHumza Yousaf faces the same questions as his predecessor (Image: PA)

The new SNP leader must, in my view, see it as a priority to convene a new Scottish Independence Convention with a representative, collective leadership/Board. Among its priorities must be setting out an unambiguous Left of Centre economic case that can secure majority support for a programme designed to redistribute Scotland’s wealth and create much more of it. 

It must reinvigorate our movement with an inspiring vision of independence based on delivering profound change, not a mini-me version of the UK state. And it must seek to win over those presently undecided and No voters with a case that is credible, attractive and has democratic self-determination enshrined within it.

And finally, in the face of the intransigence of 600 Westminster MP’s, it must mobilise that majority support via both parliamentary and extra-parliamentary means. All of this, I fully accept, takes time and an enormous amount of effort, enthusiasm and commitment.

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All the more reason for the unified Convention I advocate because that mobilisation can only be achieved by a mass movement clear on its purpose, inspired by its goal, with a determined leadership and a clear strategy for success.

That is why I call on Humza Yousaf today to inaugurate that new Convention this summer. The Scottish Socialist Party stands ready, as I’m sure others are, to play a full and productive part within it.