The only evidence we need to know that the administration is simply in CYA mode is the fact they don't seem very concerned about the "missing" WMD. If they really believed they existed, the hunt for them wouldn't be motivated by a desire to justify the war, it would be motivated by the very legitimate desire to make sure the deadly weapons were not in the hands of evil-doers. Since the administration isn't sounding the alarm along these lines, it's obvious they're unconcerned. They just want to find some scrap of something - a la the ridiculous mobile "labs" - to pacify the media and dupe the public.
If there were WMDs, and we can't find them, then we have problems.
