Nicola Sturgeon’s reaction to Boris Johnson’s disparaging and dismissive remarks about devolution made to around 60 Tory MPs on Monday night neatly summed up their potency. Scotland’s first minister said to her 1.3 million followers on Twitter it was “worth bookmarking” the prime minister’s descriptions of devolution as “a disaster north of the border” and Tony Blair’s “biggest mistake”. Those comments will not just be bookmarked, but will be printed repeatedly on Scottish National party election leaflets in next May’s Holyrood election; they will be quoted in SNP political broadcasts, parliamentary debates and, said Sturgeon, every time that a Tory minister or MP insists they respect devolution. For the Scottish Tories, and those of his colleagues in the UK government trying to reverse the steady decline in support for the union during Johnson’s premiership, such as Michael Gove at the Cabinet Office, his remarks are a disaster. For his many internal critics – including some of the Tory MPs Johnson was talking to on Monday – it was another example of his verbal incontinence, his unerring capacity for saying the wrong thing at the wrong time. The surge in support over the summer for Sturgeon, the SNP and Scottish independence – now reaching as high as 58% in the polls – has put the Tories on a war footing. They have been ruthless, summarily sacking their ineffectual Scottish Tory leader, Jackson Carlaw, and replacing him with a young MP, Douglas Ross, in an unopposed coronation. With the polls suggesting the SNP is seven months away from winning a Holyrood majority that many believe will make the case for a second independence referendum unanswerable, Ross has one job: to stop Sturgeon getting that majority. Do that, his allies argue, and they win breathing space to avert the break-up of the UK. Ross has battled to put distance between the Scottish Tories and Johnson, seemingly with Gove’s tacit support within the cabinet, repeatedly challenging the prime minister in public over difficult policies, and forcing Johnson to pressurise the chancellor, Rishi Sunak, into spending billions more on extending the furlough scheme. Ross has supported increased devolution, suggesting Scotland might have greater autonomy over immigration policy, he has supported state-funded free school meals, extending universal credit, and he has attacked Johnson’s handling of the coronavirus crisis and his lockdown strategy. The pro-union forces inside the UK government, those trying to prove the union is good for Scotland post-Brexit, had identified a series of multi-billion pound infrastructure investment plans and economic reforms they hoped would rebuild Scottish faith in the union dividend. Those include building free ports in Scottish coastal towns and cities, spending billions on upgrading the A75 trunk road, connecting Northern Ireland via the ferry terminal near Stranraer with Britain’s businesses and shops. They hoped to show Sturgeon’s government was churlishly resisting those investments. They hoped too to point at the £8.2bn in extra funding to Scotland, asking questions about the fate of several unspent billions. With two soundbites, Johnson has instead wrecked that strategy, perhaps accelerating moves within the Tory party to replace him. Those remarks remind his internal enemies he is the primary source of their crisis in Scotland. He has said similar things before. To many Scottish voters, he embodies Brexit and English nationalism, the figurehead of the UK government’s plans to over-ride Holyrood’s devolution powers post-Brexit, and, underlying that all, showing an entitled disregard for their preferences. Attacking Blair reinforces the view that Johnson has a tin ear. The then Labour prime minister was responding to Scottish popular demands for increased autonomy when he agreed to the 1997 devolution referendum. A majority of Scots voted against Brexit. A majority of Scots rejected Johnson. He may have just written Sturgeon’s election-winning leaflet.