"1) What are the chances of getting the UN to relieve the US of the burden of Iraq? Especially considering that the UN refused to go along with the US invasion and we went it alone in defiance of the UN's expressed will. Will the UN now save our bacon after so many US politicians badmouthed the UN and Security Counciil members like Germany and France so relentlessly for not going along before the war? Or might they want to see us twisting, twisting, slowly in the wind suffering the consequences? Will the "Axis of Weasels" be gracious and forgiving?"

There is no reason why Iraqis can not take over the current coalition function, other than it takes time to build a police and a miltary force. I believe the current plans are to have small miltary force trained within a few months- something like 8,000. This force will continue to train and the troop size will increase. It seems reasonable that say in about a year or two, this force could be 20,000. Meanwhile the Iraqi police force is more critical and not sure what current numbers are but they are somewhere in the tens of thousands- the Brits in South are much more successful, as are the forces in the North.
After summer is over, Iraq will be much more bearable, by Sept-Oct the worse will be over, more Iraqi police will be trained, the weather will be nearly pleasant allowing more to be done and probably making Iraq more appealing for any additional international forces. But I don't think Iraq is as much of a problem as Afghanistan, if I had to choose where to send international troops, I think Afghanistan is in more dire need of them. And if you were a soldier and had a choice of where to be deployed for next 6 months, Iraq would be an easier tour of duty.
I think we want terrorist to go to Iraq- it would be good place for them to die. So, yes we are in a very weaken postion in Iraq- oh, please, someone help us:)

"2) Is the cost worth the benefits? In other words, if you knew before the war that it would cost an extrapolated minimum of ~$100 billion in occupation costs on top of the direct war costs (as Tom would put it, money "extracted at gunpoint from American taxpayers"); and an extrapolated US death toll of more than 500 killed and more wounded, would that have changed your support for the war? In other words, knowing the cost ahead of time, would you have thought that there might be better uses for the resources to fight the war on terror and enhance US security?"

I thought it could have been easier. I thought it was possible that with coalition forces, the Iraqis could done more to overthrow Saddam regime. That would have given us, fully trained armies and police forces- which would have still needed "reform" but would be functioning. What we have is not quite as optimal, but it certainly could have been worse and in some respects is better- because we get to start with cleaner slate.
As far as cost, I think what you will find is the Miltary is using this as opportunity to go on buying spree. The operation does add costs to the normal miltary costs, this is simply something bureaucrats are well trained at taking an advantage of. I wouldn't be in the least surprised, if some unrelated black program were funded "under this cover".
Not only is there the Defense bureaucrats, you also have Congressional pork of earmarks by the boatload.