Hardtalk is in Tunisia a year after the revolution which gave birth to the Arab Spring. Stephen Sackur meets Moncef Marzouki - a man who has undergone an extraordinary transformation from political prisoner and dissident exile to president of the Republic. He now heads a coalition government of Islamists and secularists. The country has become the test bed for the new politics of the Arab world. Can Tunisia make a success of its revolution?(Image: Tunisian President Moncef Marzouki. Credit: AFP/Getty Images)