I've been reading web pages for the past hour, and have found some interesting developments regarding the WMD's and Iraq.
I have given below the links from which I draw my conclusions, please feel free to investigate and support/deny my conclusions. Just provide reasonable thought and evidence.
Saddam Hussein was in violation of UN resolutions, and refused to allow inspectors to verify that he had no WMD's. This carried on for more than 12 years. See this fact sheet from the US embassy in Latvia.
The United Nations was clearly suspicios that Iraq was acquiring or developing WMD's, in fact they "demanded unfettered access to search", something that Saddam denied them. CNN reported this on November 8th, 2002.
Yet this past March, CNN quotes a "UN weapons expert": "ElBaradei said he had been 'pretty convinced' that Iraq had not resumed its nuclear weapons program, which the IAEA dismantled in 1997." He also said: "We learned from Iraq that an inspection takes time, that we should be patient, that an inspection can, in fact, work." Refer to my link to the UN sanctions above for an estimate of how long this might take.
In March, when the US was going into Iraq, Libya began the process of dismantling a WMD buildup. Howard Dean, then front-runner for the Democratic Presidential candidate, claimed this had nothing to do with Operation Iraqi Freedom. The Washington Post reported Libya's "leader", Moammar Gadhafi, said something rather different.
"I will do whatever the Americans want because I saw what happened in Iraq, and I was afraid." Thus it seems clear that the war in Iraq did indeed decrease the number of WMD's floating, something generally beneficial to people in general, and the US in particular.
Yesterday a committee of counselors to the House of Commons released the Butler Report, a comprehensive report regarding the Weapons of Mass Destruction. It details the exchange of materials and equipment for the manufacture and distribution of WMD's amongst Libya, Iraq, and several other nations.
See paragraph 129 "In 1999, the JIC reported Usama bin Laden’s claims to be setting up a laboratory in Afghanistan."
Also note paragraph 165 that in 1991 "enough fissile material had been produced before the coalition air attacks to produce one nuclear device."
You can view Tony Blair's response to the report and download it here.
I would also like to note that the Senate would not have voted differently regarding the Iraq war if they had known what they know now. Hillary Clinton was among those who still would have voted for war.