Jonathon Rauch senior writer for the National Journal states in this solid piece that the War in Iraq was a mistake, but the right kind of mistake to make. Mr. Rauch concludes as follows:

If reasonable people thought Saddam possessed forbidden weapons, that was because Saddam sought to give the impression that he possessed them. He may have believed he possessed them. (His fearful and corrupt scientists, Kay hypothesized, may have been running a sham weapons program.) For four years after the 1991 Persian Gulf War, Iraq successfully hid its chemical weapons program. When a defector blew the whistle, weapons inspectors were stunned at the extent of Saddam’s deception. The Iraqis responded not by coming clean but by redoubling their efforts to obstruct and intimidate — for example, interfering with inspectors’ helicopter flights and, at one point, firing a grenade into their headquarters. No one could have failed to conclude that Saddam was hiding the truth.
The truth he hid, however, was not his weapons but his weakness. Or perhaps his minions were hiding his weakness from him. In either case, his power and prestige depended upon his fearsome reputation at home and his defiant posture abroad. He was contained but could not afford to let anyone know it, for fear of being invaded or overthrown. So he waved what looked like a gun and got shot.
Many people now demand to know why American intelligence was so badly fooled. The subject certainly merits investigating. Questions should be asked. Chins should be stroked. But even without an investigation, we know the most important reason we were fooled: Saddam Hussein did everything in his power to fool us, and by the time he stopped trying to fool us — if he stopped trying — it was too late for anyone ever to believe him.
The war was based on lies. Not Bush’s or the CIA’s; Saddam Hussein’s.