“It is never difficult to distinguish between a Scotsman with a grievance and a ray of sunshine,” wrote P G Wodehouse. To acknowledge the enduring validity of the Master’s observation, it is not necessary to look further than the person (personality might be an extravagant term) of Ian Blackford, leader of the SNP faction at Westminster.

Blackford is a highly recognisable type of Scot. He resembles the bore at a provincial Burns supper who buttonholes people to complain that the haggis was too dry, the toast to the Immortal Memory too frivolous and the whole event calculated to make Rabbie revolve in his grave. This year, he conceived a novel way of celebrating St Andrew’s Day, by tabling a vote of censure on Boris Johnson.