The Bush administration (by your reconning) is afraid that weapons inspectors will prove no WMDs (and thereby remove the reason for war) -- so the Bush administration rushes to war with the full knowledge that there are no WMDs, but using that as the rationale for the action, and they are putting themselves in that position knowing that they will be PROVEN wrong? ...in front of the whole world?

It's easier to get forgiveness than permission. The weapons inspectors were already well on their way to proving there were no WMD (at least none that were not already sealed by the inspectors themselves). The Bush administration knew this. The fact that the administration's actions in Iraq caused the unsecuring of weapons materials that had already been secured by the inspectors proves that the administration didn't really give a poop about the weapons. All they cared about was control of oil, balance of power, and juicy contracts for their buddies at Haliburton and Kellogg, Brown, and Root.