The lesson of London's funny but sad mayoral election

IN POLITICS, jokes can be serious. A skilful rhetorician--such as William Hague, the shadow foreign secretary--can use humour collusively, recruiting his audience via their laughter. Boris Johnson MP makes lots of jokes; many are funny, and such is his aura of shambolic wit that audiences titter even at the duds. But they are not really purposeful. They are just jokes.

Mr Johnson is the Conservatives' candidate in London's tight mayoral election on May 1st. Along with the gags, his oratorical style combines arcane vocabulary and distracted amateurism ("he's fumbling all over the place," Arnold Schwarzenegger once ...