This should be an easy one militarily but not as easy politically. Remember Desert Storm? I have heard we used something like 7-8% smart bombs vs. something like 80-90% we would use this time. Bye-bye air defense, command-and-control, pretty palaces and deep bunkers. Remember the 100 hour ground war? By the time of the cease fire, our troops were on the hills overlooking Baghdad, I am told by someone who was there, so close they could see the outskirts with the naked eye. Take a look at the map and you will realize that this is a pretty impressive feat given the suppossed might of the early-1990s Iraqi war machine.
The analysis I have heard is that Saddam's military capability is but one-third pre-Desert Storm.
Bush has been a "patient man" only to get the political aspects in order. Heck, even the Saudis said they would allow use of their military installations if/when the U.N. gets off its butt.