My solution, which I don't define as optimal, but rather making the best of a bad situation, would involve the United Nations, which will probably cause you to dismiss what I'm saying right from the beginning. But oh well, here goes.
The United States should turn over all authority to the United Nations as well as the members of the interim council without ties to Washington. That means Chalabi's gotta go. Anything else will look like the United States is trying to control the political situation in Iraq, (which right now, we are). Even then, there are valid arguments that many view the United Nations as a front for the US, but I think that most of the militants will probably go home after finding out the United States is leaving.
I think it's important to separate the militants attacking U.S. soldiers with RPGs and the people blowing themselves up outside the Red Cross. I tend to believe that most of the suicide bombers are not Iraqis resenting the occupation but rather foreign fanatics, while I think those fighting the U.S. troops directly are much more likely to be Iraqis fed up with the occupation. There have been numerous instances where members of the militant groups have gone on record after a suicide bombing to condemn it, and I think that most of them see those bombings as an evil foreign prescence similar to how they view the U.S. occupation. Even if Saddam loyalists are financing the attacks on U.S. troops, I very much doubt that most of the people fighting are Saddam loyalists, and I think that once the U.S. was out, the majority of them would no longer listen, and the resistance would lose most of it's popular support. Saddam's day is done, and I doubt very much that people will follow him back into power.
I would stop the privatization of Iraq's industry, especially to foreign companies, until such a time as Iraqis can democratically decide for themselves if that is the road they want to pursue.
As this is happening, the United States, in particular the presidential administration, should issue a formal apology to the Iraqi people and to the UN member nations. Although we will no longer be in control of the situation, we should completely finance it, because the rest of the UN shouldn't have to pay for a war we waged in defiance of international law. There should be a serious investigation into possible war crimes and human rights violations committed during the occupation. These investigations should also carry some measure of punitive power for people found to be violators.
U.S. troops may be able to stay in a peacekeeping role under UN authority, but if I were in charge I would try to replace them with foreign peacekeepers ASAP, not just because I want other countries to share the burden, or because I think trained peacekeepers are better at keeping their cool and avoiding turning residents against them, but also because I think every U.S. soldier in Iraq has the potential to serve as justification for guerrilla attacks.
I think that's kind of a start. There are plenty of other people articulating views on what should happen. And there are also plenty of people on the left criticizing ANSWER and NION. For a good read on that, go to number 8 of an article written by Michael Parenti and Stephen Shalom, called the Q&A on anti-war organizing:
http://www.zmag.org/content/showarticle.cfm?SectionID=45&ItemID=2527
The short answer to ANSWER is that, while many of us abhor their views, they're the ones with the resources, who are able to get people out. And so, on a national level, you have to attend their events and hope to win people over to your side while you're there. On a local level, I am proud to be from an ANSWER-free area, and our movement here is a homegrown one.
And once again Demo, I would just like to reiterate that it is not that the left doesn't have answers, but that the mainstream media likes to ignore them, or to turn to people who obviously don't. Again, why is it that we never here the news focus on the people at the counter-protests with signs reading "Nuke France" and "Kill All Muslims"? If that who was on TV instead of the retired generals and the presidential administration, everyone would be decrying the right as racist Nazis.