Contributor(s): Michael Scheuer | Osama bin Laden was one of America's most formidable and implacable enemies. And yet no one has written a serious assessment of his influence over world events in the last decade. Michael Scheuer; a former head of CIA's Osama bin Laden Unit provides an objective and authoritative portrait of bin Laden. Michael Scheuer was the chief of the CIA's bin Laden unit from 1996 to 1999 and remained a counterterrorism analyst until 2004. He is the author of many books, including Imperial Hubris: Why the West is Losing the War on Terrorism. His latest book is Osama Bin Laden.