The future of Britain rests on reviving the Scottish Labour Party

NO PERCH OFFERS an insight into the health of a society like a dentist’s stool. As a young practitioner in Paisley, an old weaving town outside Glasgow once famed for its teardrop-patterned scarves, Anas Sarwar would from time to time be called upon to perform “full clearances” on patients in their late teens, and fit them with dentures. The problem was methadone, a heroin substitute prescribed to addicts which is both acidic and sticky “and would pretty much fry the dentition”. The regional health board has the highest drug death rate in Scotland, which in turn has the highest in Europe.

Alleviating such misery was the historic mission of the Labour Party in Scotland, which Mr Sarwar was elected to lead on February 27th. Towns like Paisley were its firmest strongholds, reliably returning Labour MPs since the war. At its zenith 20 years ago it ran Britain. Scots filled the Cabinet, in the form of Gordon Brown, Robin Cook, John Reid and Alistair Darling, and the ranks of advisers. In 1999, the party created Scotland’s devolved government, and then ran it. It was downhill from there. In 2007, the Scottish National Party took power in Edinburgh. In the 2015 general election, Labour was swept away in a nationalist surge, losing 40 of its 41 Westminster seats. Among them was Mr Sarwar’s in Glasgow Central, a seat previously held for 13...