Why do pro-war people use the excuse that they needed to take Saddam Huseein out of power as a reason for war?

They are hoping that we all have really bad long-term memory and we'll forget about all those "We don't want to be wrong about Iraq and find out about it in a Nuclear Mushroom Cloud" talk that we heard for like 6 months.... no such luck neocons. I remember, and I'm sure a lot of other Americans do too.