Nicola Sturgeon can’t admit just how much she needs Rishi Sunak

When they met for an hour in an Inverness hotel last night, there was one thing that Rishi Sunak and Nicola Sturgeon agreed on (although neither could mention it, and Sturgeon couldn’t admit it): that it is in the interest of both of them to see Sunak stay on as prime minister after the next election.

That a Labour government of the UK would be a disaster for the Scottish National Party is one of the great unsayables of Scottish politics. Once, when Sturgeon appeared to have said it, there was such a hullabaloo that some of us have only recently got over it. It was reported in 2015 that she had told the French ambassador that she wanted David Cameron to continue as prime minister at that election.

She furiously denied it; the SNP accused the UK government of dirty tricks, as the source for the story appeared to be a note of the conversation made by a UK official at the embassy in Paris.

I doubt she said it, and certainly not as bluntly as that. But none of the sound and fury could take away from the truth of the statement that the SNP benefits from the persistence of a Conservative government of the UK. Many people in Scotland, and especially many former Labour supporters in Scotland, vote for the SNP because they object to being ruled by Tories from London. If there were a Labour government at Westminster, many of them would feel differently.

Maybe not a huge number: the SNP achieved its breakthrough in the 2007 Scottish parliament elections, just before Tony Blair left office. But if Ed Miliband had been prime minister in 2015, the SNP would probably have done less well in the Scottish elections the following year. And if Keir Starmer becomes prime minister next year, the outlook for the SNP in the next Scottish parliament elections, to be held no later than May 2026, would become significantly more adverse.

So there were more subtexts to Sunak and Sturgeon’s conversation last night than a poststructuralist dissertation. She relies on Scottish anti-Toryism for one pillar of her party’s support, and yet she has to engage with the prime minister of the UK so that she can say that she raised various matters with him – such as anti-strike legislation – but he wouldn’t listen to the voice of Scotland. At least she managed to smile in the photos with Sunak – which she tried not to with Boris Johnson – but her main aim at these events is to portray herself as the leader of Scotland meeting the leader of England as if at a parley between equals.

Sunak, on the other hand, is pursuing what Peter Mandelson called the Blair maxim: “Kill your enemies with cream.”

Boris Johnson had worked out how to handle the SNP by the end of his time in office, overcoming his early instinct for boisterous adversarialism. Sunak has gone right over to the courteous and constructive partnership approach, responding to every SNP MP in the Commons by thanking them for their question and promising to work with them for the greater good of their constituents. He lost his cool once the other day with Kirsty Blackman, when he accused the SNP of “stoking division”, but otherwise his tactic is to avoid giving the SNP anything to kick against. Anti-Toryism loses a lot of its power if the Tories won’t snarl back.

So the prime minister said afterwards that they had discussed “shared challenges”, as if the SNP were a normal party with slightly different views about gender recognition rather than a separatist party dedicated to breaking up the country that Sunak is sworn to defend. And Sturgeon said that their conversation had been “perfectly constructive and cordial”, because she doesn’t want to look as if she is starting a fight, while her supporters briefed journalists that there had been a “robust” exchange on independence.

They were both treading carefully. Sturgeon cannot rely on the hyperbolic unpopularity of Boris Johnson in Scotland any more (the former prime minister is about as unpopular as Alex Salmond, the former leader of her own party, and that is saying something). Nor did her pitched battle with Liz Truss, who delighted English Tory grassroots members by insulting Sturgeon as an “attention seeker”, ever really get started.

Now Sturgeon faces a more difficult opponent, who is determined not to interrupt her while she tries to keep her party together with an unconvincing plan to treat the next UK general election as a referendum in Scotland. At least two SNP MPs have gone public with their doubts about the plan, and there is more trouble ahead.

What she cannot say, though, is that she would rather be up against Sunak in Downing Street than Keir Starmer.