In case you’ve forgotten his role in the whole Iraq mess, Dan Darling has the following assessment:

Since the fall of Saddam Hussein, Zarqawi has emerged as the primary terrorist opponent of the United States and its allies as well as the most effective insurgent commander. His strategy has been to instigate a sectarian civil war aimed more at destroying the country than in overthrowing its government. Not content simply to kill Iraqis in order to satisfy his murderous impulses, Zarqawi and his organization have been linked to dozens of attempted terrorist attacks in the Middle East and Europe, including a thwarted chemical attack in his native homeland of Jordan in April 2004. His influence was felt as far as the recent arrests in Canada, where the Mississauga News reported that “Zarqawi’s outfit passe[d] on bomb-making manuals, advice on how to sustain terror cells and even ways to use credit card fraud to hack into vital Internet sites” to the accused terror suspects. Had he survived, Zarqawi might well have followed through on the strategy recommended to him by al Qaeda second-in-command Ayman al-Zawahiri, which called upon him to expand his war to encompass the rest of the Middle East.