Remember all this the next time you hear someone speak of London as the greatest city in the world. Chances are the words are being spoken by a politician or a celebrity or a middle-class liberal from one of the trendier parts of town.

For there are, in reality, two Londons out there. One half of it – alienated, neglected and resentful – represents a potentially formidable army at the ballot box. Who will speak for it?