Jeremy Corbyn is the most unlikely leader of one of Britain’s biggest political parties in living memory. He was elected leader of the Labour Party by a party electorate swollen by an army of new, mostly young radical members. He is a genuine socialist, anti-capitalist, anti-war; and anti just about everything that Tony Blair stood for. Stephen Sackur speaks to Lord Mandelson, one of the architects of Blair’s New Labour project. What does Jeremy Corbyn mean for Labour and for Britain?(Photo: Lord Peter Mandleson attends a service of thanksgiving for Lady Soames at Westminster Abbey. Credit: Getty Images)