Sadly, no time for detailed links to examples, but here's a fast-and-loose observation:

The Righty sites tend to argue that things are going well in Iraq; the Lefty sites tend to argue that things are going badly.

I've already commented that I think that the Lefties are radically over-estimating the strength of the following argument:

Things are going badly in Iraq
Therefore: We shouldn't be there

But, those issues aside, we should try to figure out the answer to the question: how well/badly are things going?

It's ridiculous that, with all the coverage of Iraq, we don't know the answer to this question. Of course, there are a couple of major impediments standing between us and the knowledge we seek. Among them:

(A) We can no longer trust what the Administration tells us about Iraq

(B) The Big Media, as usual, tend to focus on the spectacular rather than the quotidian, so we hear far more about deaths and explosions than soccer games and marriages

But another problem is:

(C) Most of us have little idea what counts as going well and going badly in a case like this.

A Republican-yet-intelligent friend of mine who knows his history tells me that we lost a lot of men in the occupation of Germany after WWII. Some of the Righty sites have noted that after WWII there was a lot of we're-losing-the-peace
stuff flying around, too. A Lefty friend tells me that the Lefties are saying that we lost NO men to enemy fire in the occupation of Germany. We might be able to triangulate on this issue by answering that eminently answerable empirical historical question: how many men did we really lose in the occupation after WWII? The analogy is imperfect, of course: Gulf War Episode II is not WWII. But if we really did lose few men after the fall of the Third Reich, then it suggests that
we should count the occupation of Iraq as relatively difficult--though, as I've said, we have to be careful about what conclusions to draw from that. On the other hand, if the occupation of Germany was lots worse, this might suggest that
occupations of this kind are generally tough, and, consequently, that the difficulty of the matter per se shouldn't cause us to panic overmuch.

Just some suggestions. I'll try to find some links when I get some time.