KABUL, Afghanistan, July 10 - Journalists remember him as Jack, an eccentric, heavily armed and at times, it seemed, dangerously unbalanced, middle-aged former American Special Forces soldier, who appeared in Afghanistan in the fall of 2001. Surrounded by armed Afghan guards and rumors that he worked for the Central Intelligence Agency, he quickly rose to prominence. In the next two years, he was interviewed by Fox and CBS News, helped write a book called "The Hunt for bin Laden" and said he had discovered evidence in Afghanistan that linked Iraq to Al Qaeda. This week, Jack, a convicted felon...