Excerpt from interview with Peter Bergen, author of "The Osama Bin Laden I know: Inside the secret world of Osama Bin Laden" by Frank Stasio on National Public Radio. Peter Bergen: "(Abu Musab al-Zarqawi and Osama Bin Laden) had sort of philisophical differences and they competed for money ... they really only came together as the Iraq war heated up and Zarqawi never swore an oath of allegiance to Bin Laden until 2004, two years into the war. So, Colin Powell had, at his famous U.N. presentation, said Zarqawi was the best evidence for this sort of Al Qaeda/Saddam Hussein...