That is an idiotic rationalization. The only reason he knows for sure that there have been no WMD found in large quantities is that we invaded in the first place. Had we not invaded we would STILL be dealing with the pre-war intelligence that stated he had them. As to post occupation woes, NO one said it was going to be a damned cake walk and the moment the first sign of an insurgency cropped up the Democrats and Media IMMEDIATELY started with the Quagmire crap and the more they pushed it the harder the insurgents fought to make it so.
You see, the first time I heard the phrase "weapons of mass destruction" cross the President's lips I recognized it for exactly what it was: a catch phrase to secure political support from the same dopey soccer moms who had supported Bill Clinton throughout the 1990s. He used that silly phrase to arouse fears among those morons whenever he felt a need to look manly and important to suburban women -- with IQs of about room temperature -- whose biggest fear in life was anything that threatened their kids, their homes, their trips to the nail salon, etc.