Well I don't want to overstress the analogy to America, since I realize that Iraqi culture is different than ours.
But in all fairness to them, there were multiple times when the good guys in our revolution were beaten back, scattered and and sent running at full speed. The British were congratulating themselves on their victories. And any of our allies would be justified to say, "The Americans won't fight for their freedom - the past week has shown that."
All I want to say is that these conflicts of freedom vs. tyranny can take many years and decades. We won't know for a long time how Iraq will turn out. And I think it could go either way.
Along the way there will be good days and bad days, and plenty of people will make the most of the bad days. But I think most Americans know to keep an eye on the long term -- most Americans are pretty level-headed about this sort of thing, and same same goes for key allies like the UK.