Ion

The crux of the matter comes down to this:

1) Bush claimed that he knows of WMDs in Iraq, then broke the U.N. Chart Article 51 that allows a U.N. member to war only in self-defense when Bush attacked Iraq to find no WMDs.

In fact Bush's rush to war is motivated by oil.

2) U.N. claimed it doesn't know of WMDs in Iraq (see the U.N. Security Council opposing Bush's drive for war in February 2003), wanted to inspect for them (so "...all corroborated the intelligence obtained after years of inspections and intelligence from defectors...", it's wrong), and is proven right now when Bush doesn't find WMDs.

Sauron

Benefit of the doubt not needed. We can go off the reports of the UN inspectors, who found no evidence of their existence, nor any evidence that Iraq was hiding them.

Which is another reason that Dubya opposed sending inspectors in - because the administration already knew that no such WMDs would be found. Having inspectors go in and find nothing would undercut Dubya's public statements. So the administration fought the UN inspections every way it could.