Iraq was not a “side trip” ... Iraq via Iran was where al Qaeda active leadership went after Tora Bora, and even before. Iraq was where we Abu Nidal was, and he had attacked the US before. Iraq was where the perp in charge of the WTC bombing of 1993 was. Iraq was where some of those involved in the bombing of the USS Cole were caught. And Iraq was where Zawahiri was, and he was the guy involved in numerous things, including the millennium plot to blow up the LAX airport, blow up Us facilities in Jordan and was the guy who assassinated US Aid official Lawrence Foley a year before the war.
Zawhiri is well traveled. A while ago I read he was married to a woman in the tribal areas of north West Pakistan, and was under their protection as a kinsman. Any idea where he is now.