CHEERING crowds flock to his rallies. Youngsters embrace him for selfies and hang on his every tweet. Jeremy Corbyn, improbable, crinkly rockstar of the far left, is on course to be re-elected Labours leader on September 24th in a landslide vote among the partys members, hundreds of thousands of whom have joined up in the past year just to back him.
Yet Mr Corbyns popularity among Labours half-million members and affiliates is not replicated among Britains 45m voters, most of whom do not share his desire to overthrow capitalism and unilaterally forsake the countrys nuclear weapons, nor his soft spot for strongmen such as Vladimir Putin and the late Hugo Chávez. The party is polling at its lowest in opposition for 30 years. Among young people, his most sympathetic constituency, Mr Corbyn has an approval rating of -18%. Among the over-65s it is -68%. Labour is on course to lose scores of seats at the next election. And it will not end there. Parties often pick bad candidatesmainstream Republicans recoil at Donald Trump, for instancebut it usually costs them no more than one election. Mr Corbyn, by contrast, is packing Labour with allies and seems more concerned with building a long-term movement than winning power. The Conservative government can expect years without being seriously challenged in Westminster.
The story of how one of the most reliable vote-winning machines in the West drifted into irrelevance is a warning to parties everywhere. It is a tragedy for Labour, which under its recent centrist leaders was in power for 13 years, introducing reforms from a minimum wage to gay unions. And it is bad news for Britain. Experience, from Mexico to Japan, suggests the long-term absence of serious political opposition leads to bad government. Worse, Labours meltdown comes as Britain begins complex and perilous Brexit negotiations, which need scrutiny. What opposition there is will come from the Tories eccentric fringes and from the undemocratic House of Lords. And Scotland may wonder more than ever why it should remain attached to its Brexiteering big brother.