According to the New York Times, the fact that Zarqawi dropped out of high school and that the U.S. raised the bounty on his head to $25 million are " key events" in his life. But his arrival in Iraq and his stay in Baghdad prior to the March 2003 invasion, with the approval and perhaps assistance of the Iraqi regime, are not. General Tommy Franks evidently believed it was enough of a "key event" to note in his memoir American Soldier:
One known terrorist, a Jordanian-born Palestinian named Abu Musab Zarqawi who had joined al Qaeda in Afghanistan -- where he specialized in developing chemical and biological weapons -- was now confirmed to operate from one of the camps in Iraq. Badly wounded fighting coalition forces in Afghanistan, Zarqawi had received medical treatment in Baghdad before setting up with Ansar al Islam. And evidence suggested that he had been joined there by other al Qaeda leaders, who had been ushered through Baghdad and given safe passage into northern Iraq by Iraqi security forces....[p. 332] And while many al Qaeda leaders had been killed [in Afghanistan], others had sought sanctuary in Iraq. [p. 403]