Can Florence’s youthful mayor save Italy from herself?If ever a country’s politics needed a shot in the arm, it is Italy’s. As the economy wobbles on the brink of catastrophe, we Italians are desperate for a new face from outside the discredited political caste: an Italian Obama, if you like. But who could possibly step into the breach? Some eyes are turning towards Florence’s handsome young mayor Matteo Renzi, who at 36 makes David Cameron and even George Osborne look like grizzled veterans. To go from running the world’s most beautiful city to leading the world’s most ungovernable country would be a huge, and daunting, step. In Italy politicians are supposed to form an orderly queue and wait their turn for the top jobs.