It is ten years since the two mighty towers of the World Trade Center were reduced to dust and ash. On 9/11 Osama Bin laden inflicted a grievous wound on the United States. This week the US is immersed in memories of the attack and what came after. In this special edition, HARDtalk meets the Mayor of New York City on its darkest day, Rudy Giuliani. His response back then earned him the title 'America's mayor' and he won worldwide admiration. Ten years on, how much have he and his country been changed by 9/11? Rudy Giuliani talks to Stephen Sackur. Show less