"I believe demolishing Hussein's military power and liberating Iraq would be a cakewalk. By Ken Adelman (assistant to Defense Secretary Donald Rumsfeld from 1975 to 1977, and arms control director under President Ronald Reagan) in the Washington Post Wednesday, February 13, 2002.
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"I can't tell you if the use of force in Iraq today will last five days, five weeks or five months, but it won't last any longer than that." Donald Rumsfeld, Sect. of Defense, Nov. 14, 2002.
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"Saddam is much weaker than we think he is. He's weaker militarily. We know he's got about a third of what he had in 1991."

"But it's a house of cards. He rules by fear because he knows there is no underlying support. Support for Saddam, including within his military organization, will collapse at the first whiff of gunpowder.        Richard Perle, recently resigned chairman of the Defense Policy Board, in a PBS interview July 11, 2002
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"This will be no war -- there will be a fairly brief and ruthless military intervention.

"The president will give an order. [The attack] will be rapid, accurate and dazzling ... It will be greeted by the majority of the Iraqi people as an emancipation. And I say, bring it on. Christopher Hitchens, Vanity Fair writer, in a debate Jan. 28, 2003:

I could chase around and find more. Of course, so far as the actual initial victory goes, they are accurate enough (which is hardly surprising given the disparate of military resources of the two sides - though that kind of confidence does seem to indicate that those fampous "Weapons of Mass Desruction" were not always seen as constituting a real threat, by those in the know). But the clear implication of those quotes was that this blitzkrieg victory would mean a rapid the end of the war and transition to peace.

And when Bush went to Iraq on that visit where he drssed up as a pilot and declared victory back in May 2003 there was the same clear assumption that things were pretty well sorted out. Whereas in a real sense they were only starting.

I don't think there were too many advocates of the war who said before it started that they thought it would last for many long years, and mean thousands of dead among the occupying armies. (Let alone the far higher numbers of Iraqi dead.)