|Despite the finding by the 9/11 commission staff that there is no evidence of a "collaborative relationship" between Saddam Hussein and Al Qaeda, Bush administration officials continue to insist the two worked together. As evidence, they frequently cite Abu Musab al-Zarqawi, the 37-year-old Jordanian who is arguably the most dangerous terrorist in the world today. Mr. Zarqawi, who fled his Afghan training grounds after the American invasion and found safe haven in Iraq, was most likely behind the string of bombings across Iraq on Thursday that killed more than 100; in May, he beheaded Nicholas Berg, an American communications engineer working in Iraq.
The day after the 9/11 staff report came out, Vice President Dick Cheney again put forward Mr. Zarqawi. "After we went in and hit his training camp, he fled to Baghdad," Mr. Cheney said, adding that Mr. Zarqawi "ran the poisons factory in northern Iraq out of Baghdad." The administration has also pointed out that American intelligence believes Mr. Zarqawi received medical treatment in Baghdad in 2002.
So is Abu Musab al-Zarqawi really the missing link between Al Qaeda and Saddam Hussein? Actually, the evidence of his relationship with either is far from clear cut. Mr. Zarqawi runs an organization separate from Al Qaeda called Tawhid. One indication of his independence is that when he founded his training camp in Afghanistan in 2000, he did so near the western city of Herat, on the Iranian border, hundreds of miles away from Al Qaeda's camps.
Roger Cressey, who was a counterterrorism official on the National Security Council staff at that time, told me that Mr. Zarqawi's camp was set up "as much in competition as it was in cooperation" with Al Qaeda. Indeed, Shadi Abdullah, a Tawhid member apprehended in Germany in 2002, told investigators that his group saw itself to be "in rivalry" with Mr. bin Laden's, according to a German official privy to the details of the interrogation.
And in January, American forces found a letter believed to have been written by Mr. Zarqawi to Al Qaeda leaders hiding on the Afghanistan-Pakistan border. It requested aid in fighting the Shiites of Iraq: "You, gracious brothers, are the leaders, guides and symbolic figures of jihad and battle. We do not see ourselves as fit to challenge you if you are convinced of the idea of fighting the sects of apostasy; we will be your readied soldiers." The tone of the letter is clearly that of someone outside Al Qaeda appealing for its help. And Al Qaeda's leaders seem little interested in fomenting a Sunni-Shiite civil war in Iraq; in the audiotapes he has released in the past year, Osama bin Laden has made no mention of the Shiites.
"The central question the administration has failed to answer is: Was there guidance or direction from the Al Qaeda leadership to Zarqawi?" Mr. Cressey, the former counterterrorism official, told me. "The evidence presented so far is there was not." At a briefing on June 17, Secretary of Defense Donald Rumsfeld seemed to agree with that assessment, saying of Mr. Zarqawi that "someone could legitimately say he's not Al Qaeda."
Mr. Zarqawi's connections to Saddam Hussein are equally tenuous. After fleeing Afghanistan, he probably spent as much time living in Iran as in Iraq. What Mr. Cheney described as the "poisons factory" Mr. Zarqawi ran was actually in the Kurdish area of northern Iraq, an area protected by American jets since 1991. Mr. Rumsfeld had more control than Saddam Hussein over that part of Iraq.
As for the medical treatment Mr. Zarqawi supposedly received in Baghdad, for some time American officials thought it was a leg amputation. However, the footage of Mr. Zarqawi in the video of Mr. Berg's execution seems to show a man in possession of both limbs. And last week Mr. Zarqawi released an audiotape on a jihadist Web site containing a blistering critique of Saddam Hussein, whom he described as a "devil" who "killed the innocent."
Mr. Zarqawi is a ruthless murderer, and capturing or killing him would be a major step toward pacifying Iraq. But if he is, as President Bush has said, the "best evidence" of a link between Saddam Hussein and Al Qaeda, the administration's case is a weak one.
Peter Bergen is a fellow at the New America Foundation and the author of "Holy War Inc.: Inside the Secret World of Osama bin Laden."