Pachomius, your comment is a classic case of the Big Lie wins again.
Saddam Hussein did not close his doors to regular U.N. inspections, ask chief inspector Hans Blix, he was there. The Inspectors left suddenly when the received news of the imminence of Operation Iraqi Freedom. They wisely decided to avoid being bombed by the United States. Repeating the lie doesn't make it true regardless of how you define Truth.
Saddam had one very good reason to be evasive about his possession of WMD's: Iran. Countless members of the intelligence community, the State Department, DOD and Bush's own cabinet knew understood this. The point is, the facts and any nuanced analysis thereof didn't matter to the Bush administration. You'll get no argument from virtually anyone opposed to this misadventure that Saddam Hussein was a despicable despot. The argument has always been that invading Iraq had nothing to do with what the administration claimed it was about and that it was illegal, unjust, deadly, expensive and foolish.
The history of the Republic is littered with the wreckage of similar deceit: Mexico, Spain, Tonkin Gulf, etc., lying us into war has never been perceived as a criminal offense for a U.S. president. But let's not deny demonstrable fact either.