Saddam's supposed possession of WMD was reported by numerous intelligence agencies world-wide. Jordan, Russian, Brit, US, Israel and more were all certain that he had WMD and would use them in the region. He DID use chemical WMD against his own people in Northern Iraq. It was also reported that he purposely inflated reports of amounts in his possession in order to frighten his neighbors in the region. It makes perfect sense all taken together, and WMD was only one of the many reasons we went in there.