Ok, first of all, US was trying to actually enforce the resolutions that the UN has passed, but is spineless to do anything about. Sadam voluntarily agreed to do a bunch of things in 91 as part of the cease-fire agreement with the US and UN, every word of which he has broken. When the US tried to pass a resolution that would set firm deadlines for Saddam's disarmament, France and Russia vowed to veto it in the Security Council.
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