The Bush administration's claim was that all Iraqi Army units could deploy chemical weapons within 45 minutes. That's a very real and very persuasive threat. But if it's true surely to goodness there'd be some evidence of that capability by now, instead of evidence of only protective measures.
The Iraqis had NBC suits stored near the frontline. Iraqi troops have been captured and killed carrying respirators. How exactly does that differ from what our troops are doing? Yes I know that we were not ever likely to use gas against the Iraqis, but can we assume so readily that they know and believe that?
The balance of probability does suggest that the Iraqis are far more likely to use WMD than we are, but there seems to be no evidence so far that they actually had any plans to do so, or that they had deployable chemical weapons in place with frontline forces. Their possession of protective equipment does not (in itself) constitute such evidence.
I hope that we do find such evidence - it would justify everything that Bush and Blair have said and done.