Best editorial I've seen on the weapons hunt from today's Washington Post. Was the administration wrong about what we'd find in Iraq. Yes. Do the administration and the intelligence agencies have a job to do to determine what went so wrong? Yes.
Equally, was Saddam still pursuing WMD? Yes. Was he a threat? Yes, but that threat would have been much greater once he had received a clean bill of health from the UN and the inspections/sanctions regime was lifted.
This is the most difficult part of the whole enterprise. The administration knew it had to tackle Saddam, knew he was no good and was sure he was doing something, but they never really knew what it was. After September 11 they had to remove Saddam because of his character and that was the long and short of it.