Wollcott links opinion on the mechanics of withdrawal by Martin Crevald:
http://jameswolcott.com/(says Martin Crevald:) "Handing over their bases or demolishing them if necessary, American forces will have to fall back on Baghdad. From Baghdad they will have to make their way to the southern port city of Basra, and from there back to Kuwait, where the whole misguided adventure began. When Prime Minister Ehud Barak pulled Israel out of Lebanon in 2000, the military was able to carry out the operation in a single night without incurring any casualties. That, however, is not how things will happen in Iraq.
"Not only are American forces perhaps 30 times larger, but so is the country they have to traverse. A withdrawal probably will require several months and incur a sizable number of casualties. As the pullout proceeds, Iraq almost certainly will sink into an all-out civil war from which it will take the country a long time to emerge — if, indeed, it can do so at all. All this is inevitable and will take place whether George W. Bush, Dick Cheney, Donald Rumsfeld and Condoleezza Rice like it or not."
snip
(Crevald) "For misleading the American people, and launching the most foolish war since Emperor Augustus in 9 B.C sent his legions into Germany and lost them, Bush deserves to be impeached and, once he has been removed from office, put on trial along with the rest of the president's men. If convicted, they'll have plenty of time to mull over their sins."
Nuremberg II, anyone?