Election 2021: Alex Salmond's potential return to Holyrood is Nicola Sturgeon's worst nightmare

It must be Nicola Sturgeon's worst nightmare – not just the sudden entry into the election campaign of her mentor-turned-nemesis Alex Salmond but his potential return to Holyrood, expecting to play a key role in bringing about independence.

Alex Salmond launched the Alba Party on Friday

The former First Minister clearly hopes his new Alba party will not only help win a “super majority” for independence and pave the way to a second referendum, but also that it will put him back in the Scottish Parliament and allow him to influence events.

After being cleared of breaching the ministerial code, Ms Sturgeon wanted to put her bitter fall-out with her predecessor to one side and focus on the election, but instead the Salmond-Sturgeon “psychodrama” threatens to dominate the campaign and could intensify afterwards if Mr Salmond is elected as an MSP.

There is a logic to the strategy Alba has announced of fielding its own list candidates in the hope of winning the "wasted" votes of SNP supporters to get more pro-independence MSPs elected.

It’s not a new idea – there were already two new parties with candidates declared for this election with exactly the same purpose. One of them, Action for Independence, has now withdrawn and thrown in its lot with Mr Salmond, though it seems most of its candidates will not be adopted by Alba.

Whether it will work or not is another matter. Polling guru Professor Sir John Curtice has warned Alba could take votes away from the SNP, depriving it of a crucial handful of list seats without the new party picking up any of them. And he has suggested the SNP winning an overall majority on its own – the situation which led David Cameron to agree to the 2014 referendum – may be more important than a super-majority made up of several pro-independence parties.

Sir John has also argued Alba’s success will depend largely on Mr Salmond’s own popularity and pointed out polls show only 14 per cent have a favourable view of him. Another poll found his approval ratings were below those for Boris Johnson. By highlighting the divisions in the Yes camp, Alba’s intervention could also put people off voting for the SNP or independence.

But even if it does help achieve a super-majority for independence, there seems little reason to believe the Prime Minister will agree to a new referendum. It could be argued a super-majority has existed for the past five years with the combined numbers of the SNP and the Greens, but Mr Johnson has refused even to discuss the required Section 30 order.

Mr Salmond has said he hopes to help write the prospectus for independence ahead of a referendum and Alba is expected to publish a policy platform which he would no doubt pursue if elected. But after all that has happened between him and Ms Sturgeon over the past year there can be no renewal of the old partnership and just their presence in the same parliament would mean constant tension.

No-one can take away Mr Salmond’s huge achievement in transforming the SNP and coming closer to winning independence than anyone expected. But his attempted comeback is highlighting the divisions in the nationalist movement and threatens to undermine its chances of success.