Matthews hasn't "turned on a dime" -- he has always been critical of the rationale for war. He may be playing naive viewer now for effect.
Yes he can be an ass sometimes.
But here's an example -- to Torie Clark, Pentagon Flack Feb 8 2006. Somewhere there is video of it. ON EDIT: VIDEO HERE and well worth watching:
http://www.crooksandliars.com/2006/02/08/chris-toasts-torie/Chris toasts Torie
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Chris Matthews toasted Torie Clarke on Hardball today. It takes a couple of minutes until they finally get into the debate on Iraq.
Video-WMP Video-QT
She completely abandoned the WMD claim and based it on a “pre-emptive war” strategy. He shot down all the arguments the administration used to get us into Iraq and called it a great “sales job.”
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http://www.msnbc.msn.com/id/11256228/All the arguments about W.M.D. have been shot down. No evidence of an African deal, no evidence involving aluminum tubes. All the arguments that your side put up to get us into this war have been shot down, especially the argument that we were going to be received by people who are going to be happy to see us. They are fighting us. They are not happy to see us. That the oil in America was going to be cheaper. That the oil was going to pay for the war itself.
You‘re crowd made every argument in the world to get us in that war, and then they all quit. What I can‘t understand is how an administration packed with hawks, they are all gone. Scooter is facing jail. Wolfowitz is gone. I don‘t know what else is gone, but all the hawks seem to be gone now.