Bill de Blasio, sometime supporter of the Sandinista revolution in Nicaragua, will soon take over as mayor of New York. He's overcome the suicide of his war veteran father, created the most famous multiracial family in the US and now has to persuade Wall Street to fund his radical plans to overcome inequality in the Big Apple. Ed Miliband is said to be watching carefully. Mark Coles profiles a politician attracting global attention.

Producers: Ben Crighton, Chris Bowlby