During the 1991 Gulf War when American and British forces removed Saddam from Kuwait, the Father Bush administration suddenly stopped the war before they continued to Baghdad to remove Saddam. They did this because the plans for what is unfolding now were already in place and they needed Saddam to still be there to justify the invasion of Iraq in 2003.
They therefore needed to explain why they did not remove Saddam in 1991 and here is Bush Defense Secretary Dick Cheney making the case for leaving Saddam alone.
It is a wonderful example of how they change the story to fit the outcome they want.