Humza Yousaf might have hoped for a better week. On Wednesday, the First Minister gave a speech at the European Institute of the London School of Economics, setting out why Scotland’s economic future would be brighter if it was an independent country. Some in the room were enthusiastic, but the Scotsman quietly drew attention to an LSE study from 2021 which had found that ‘the economic costs of independence are two to three times greater than the impact of Brexit’.

The report went on to conclude that independence would mean ‘an income loss of between £2,000 and £2,800 per person every year’ and that it would make little difference whether an independent Scotland was a member of the European Union or not. Its LSE origins were an unfortunate resonance, and in any event many observers felt that Yousaf had failed to make his economic case.

Is Yousaf a cause or symptom of an SNP running out of momentum?

The following day brought a double whammy. A Redfield & Wilton Strategies poll found that Scottish Labour leader Anas Sarwar had for the first time nudged ahead of former schoolmate Yousaf in preferences for first minister, at 32 per cent to 31 per cent. The research also put Labour and the SNP level on voting intention for the general election, which would give Labour 27 seats and the Nationalists only 20. Head to head, Yousaf only outpolled Scottish Conservative leader Douglas Ross by 36 per cent to 30 per cent.

The final blow was the judgement from the Scottish parliament corporate body that Michael Matheson, the health secretary who resigned in February, had breached the code of conduct for MSPs over a £11,000 bill for his parliamentary iPad. The First Minister had been doughty in his defence of his minister, who had ‘served this country and served this parliament for decades’. That now looks like a bad call.

There are two things happening. The first, so far as the Scottish National party is concerned, has a lot to do with fatigue: the Nationalists have been in power at Holyrood for nearly 17 years. The relative star quality of Yousaf’s predecessors Alex Salmond (2007-14) and Nicola Sturgeon (2014-23) for many years insulated the party from damaging criticism.

It is not that the Scottish government has made no mistakes. Two ferries ordered by the government to serve the passenger routes of the Hebrides in 2015 have been plagued by cost overruns and delays, and are not yet in service. In 2020, it emerged that Scotland had more deaths from drug overdoses per head than anywhere in Europe, a rate which had doubled since 2014. And a report from the Institute for Fiscal Studies last December found that the educational attainment of Scottish children, especially in maths and science, was declining.

Of course the SNP refutes or explains away these failures. Politically, one would expect no less. What is significant is that, until the last days of Nicola Sturgeon’s tenure as first minister, this was successful. The party won a majority in the Scottish parliament in 2011, something that was supposed to be impossible under its electoral system, took all but three seats in Scotland at the 2015 general election and retained power at Holyrood in 2016 and 2021.

The political crisis over Sturgeon’s Gender Recognition Reform (Scotland) Bill, which was prevented from attaining royal assent by the intervention of the UK government, may have been an indication that something was changing. The then-first minister seemed less sure-footed and more vulnerable than previously. In February 2023, she resigned.

Humza Yousaf, former health secretary and justice secretary, was narrowly elected to replace Sturgeon (52/48, a familiar ratio). It was a tense and rancorous contest: his opponent, finance secretary Kate Forbes, was heavily criticised for her religious beliefs. As he approaches his first anniversary in office, the First Minister looks beleaguered. He is not a lucky politician, whether through physical pratfalls tumbling off a knee scooter while racing to vote in 2021 or tweeting-then-deleting condolences to a Glasgow gangland figure in 2020.

He is prickly, too. His first response to criticism, however well- or ill-founded, seems to be aggression. A recent story about Scottish government payments to the UNRWA in Gaza was an ‘Islamophobic attack’, ‘an outrageous smear’ and a ‘far-right conspiracy’. When the Hallett inquiry into Covid-19 revealed that Yousaf admitted in a text message ‘I am winging it!’ (he was cabinet secretary for health), he attacked Boris Johnson’s leadership and praised that of Nicola Sturgeon.

Is Yousaf a cause or symptom of an SNP running out of momentum? The result of the general election will be significant, but for the Scottish government the real test will be the polls for Holyrood in 2026. Can the SNP afford to leave Humza Yousaf in office until then?