1. Would you concede that Iraq had WMD before Gulf War I?
2. Would you concede that a large number of these weapons were unaccounted for when the inspectors left in '98?
3. What do you suggest Iraq did with those weapons? Do you really think Iraq destroyed them and just decided not to show us just to be petulant?

Just because we haven't found the weapons (yet) doesn't mean they didn't exist. You can argue that they were shipped off to Syria, or you can argue that they were destroyed and Saddam was just to stupid or egotistical to show us, but I don't think you can argue that they didn't exist in the first place.