Why wouldn't Saddam prove he destroyed his WMD program?

In the run-up to the Iraq War, it was often asked by proponents of the war, “Why doesn’t Saddam just come out and prove that he doesn’t have WMD?” They believed he wasn’t fully complying with our demands, and that meant he was hiding something. Forget, for the moment, that there was probably nothing Saddam could have done to quiet down the dogs of war. As an honest question, I think it is important to try and answer it, especially since the now definitive answer is that there never were any WMD. Juan Cole puts forth what I think to be a reasoned answer to the question.
The main reason for which he would not provide proof of the destruction of chemical weapons stockpiles, he told the group, was that he was worried about Iran. Apparently he never got over the trauma of the Iran-Iraq War of 1980-1988, when he came close to being defeated by his much bigger neighbor. (Only the Reagan Adminsitration alliance of convenience with him saved him). And, of course, his anxiety about Iran was in part a code for fear of a Shiite uprising. Saddam was fighting several Shiite revolutions, being mounted by the Sadrists, the Supreme Council for Islamic Revolution in Iraq, the al-Da`wa Party, and the Marsh Arab Hizbullah. He was barely able to keep a lid on them, using secret police and brutal repression. They were being backed by Iran (or at least all but the Sadrists were), and he was admitting that he feared that if the Iranians and the Iraqi Shiites thought he would not be able to gas them, he might be open to another invasion or a popular Shiite uprising. The group report says Saddam used chemical weapons on the Shiites to put down the rebellion of spring, 1991. (What it does not say is that the United States, which was in a position to stop this use of WMD on civilians, as well as the use of conventional weapons to massacre thousands, declined to so much as fire a missile at a helicopter gunship). Ironically, the Sadrists and Marsh Arabs have gone on to pose a dire threat to order in post-Saddam Iraq, and the US has also treated them harshly as a result. Saddam also was appears to have been convinced that the US would not attack his regime after September 11, because of its secular character. Saddam is often caricatured as a madman (and it is true that there is something wrong with the man), but in this remark he shows himself thinking rationally and expecing Bush to do the same.
I think this is a solid answer to the one question that seemed to confound even the most stringent anti-Iraq War advocates. Saddam was never a world-domination sort of guy, despite all the nasty rhetoric from this Administration. Containment and sanctions were working, and the strength of his regime was only a fraction of what it used to be. Saddam’s primary concern was maintaining his power of Iraq. It seems that his biggest miscalculation was believing Iran posed the greatest threat to his power, and not the US. He certainly miscalculated the intensity and depth of the desire among certain people in the Bush Administration to invade Iraq. Maybe he thought we weren’t stupid enough to invest so much of our resources to displacing him, when we had Osama bin Laden and al Qaeda to worry about. Frankly, neither did I.