He was speaking in the same way that the military always speaks when you don't know where each weapon is deployed - especially when even a few dozen can have a significant effect. Did we know they had WMDs? Yes. Did we know that they had weapon systems designed to be pulled out of their crates and launched within 45 minutes of the local soldiers being told to do so? Yes. Do we know exactly how he has tehm deployed on a given day? No, and it really doesn't matter unless we can confirm they've set up to launch...in which case, we don't bother to take it to Congress, or to the people - the President takes immediate action and explains it later.