Novelist Andrew Klavan suggests:

In all fairness, moviemakers have a legitimately baffling problem with the nature of the war itself. In order to honestly dramatize the simple truth about this existential struggle, you have to depict right-minded Americans — some of whom may be white and male and Christian — hunting down and killing dark-skinned villains of a false and wicked creed. That’s what’s happening, on a good day anyway, so that’s what you’d have to show.
Moviemakers are reluctant to do that because, even though it’s the truth, on screen it might appear bigoted and jingoistic. You can call that political correctness or multiculturalism gone mad — and sure, there’s a lot of that going around. But despite what you might have heard, there are sensible, patriotic people in the movie business too. And even they, I suspect, falter before the prospect of presenting such a scenario.
We cherish the religious tolerance of our society, after all. Plus, we’re less than a lifetime away from Jim Crow and, decent people that we are, we’re rightly humbled by the moral failures of our past. We’ve become uncomfortable to the point of paralysis when reality draws the limits of tolerance and survival demands pride in our traditions and ferocity in their defense. We can show homegrown terrorists in, say, “Déjà Vu” or real-life ones, as in “United 93,” but we can’t bring ourselves to fictionalize the larger idea: Islamo-fascism is an evil and American liberty a good.

All it would take, I think, is one filmmaker willing to do what Mel Gibson did with Passion of the Christ: break with the timid studios and make a film about the war on terrorism that succeeds at the box office. Not Mel, of course — just someone willing to buck the studios like that. (h/t Hot Air)