This statement was actually exposed as disingenuous before the fact by Scott Ritter, former UN weapons inspector and early victim of the Rove slime machine.
On July 17, 2002, Ritter explained:
"Well, look: As of December 1998 we had accounted for 90 to 95 percent of Iraq's weapons of mass destruction capability -- "we" being the weapons inspectors. We destroyed all the factories, all of the means of production and we couldn't account for some of the weaponry, but chemical weapons have a shelf-life of five years. Biological weapons have a shelf-life of three years. To have weapons today, they would have had to rebuild the factories and start the process of producing these weapons since December 1998."See the Wikipedia article on Ritter for a fuller quote and more info:
http://en.wikipedia.org/wiki/Scott_RitterBy the time the President uttered that nonsense, the chemical and biological weapons Saddam could have had were useless. That didn't stop the President from repeating the allegation in his State of the Union Address almost four months later.