"WMD-wise, Iraq turned out not to be a direct, imminent threat to the United States."

If Saddam's regime had not signed the cease fire agreement which included as part of the agreement the section pertaining to WMD, then the WMD by itself would have unlikely to have been considered as an important issue.
Had Saddam followed the cease fire agreement, there would have been no sanctions and the "No Fly Zones" would have ended shortly after Gulf war I.
The reason the Clinton Administration recommended regime change in Iraq, was not because Saddam had WMD, but there was perception that Saddam would not abide by treaty type agreements [the cease fire agreement is a treaty type agreement].

I realize that the UN in general terms is a cluster fuck, and I personnally had concerns that Saddam may have actually tried to complied with the cease fire agreement as much as can be reasonably expected but was hindered due to perhaps idiocy and incompentency of UN bureaucracy. But because these WMD later were found in Iraq, it does validate Blix's unwillingness to declare that Saddam's regime had fully complied with the cease fire agreement.

Now, what could be challenged was orginal idea of including WMD provision in the cease fire agreement- perhaps the part about missiles was too much, maybe it should focused solely only a nuclear weapons. But if the agreement included a requirement that Saddam wear a pink dress every Tuesday, and that was agreed upon, then Saddam should be required to wear a pink dress every Tuesday.

But as far as a direct, imminent threat [disregarding Saddam's willingness to violate international treaties- and that he said in public that Iraq was at war with America]. Saddam's desire to make nuclear weapons [and use chemical weapons in warfare or against civilians] and his access to oil wealth that enabled to do this, was a threat, but not imminent. And most of the threat was indirect- as in potential things that would shocked the world into global depression and potential chaos that could result [see WWII].

Perhaps, America, as world's sole superpower, unwillingness to regard treaty agreements as a serious matter presented the biggest and nearest term threat. E.g. what could it mean in regard to Tiawan/China? And/or what consequences does it have in regard to our allies in the middle east region on the whole?