Read through the Wikipedia articles on V for Vendetta (the graphic novel and the film) and I can understand better why Alan Moore refused to be associated with the movie. As a condensation of the series, the film works moderately well; as an anti-W polemic, it's epic fail.
Pretty simple, actually. Nobody who isn't already a 9-11 truther (or similar wackjob) is going to buy the Norsefire::Republicans analogy, and there's way too much UK-specific imagery & background for anyone to buy into it as a version of America. "Remember, remember the 5th of November!" has zero resonance on this side of the Atlantic, and the same goes for the omnipresent BTN (BBC). The sly references to America disintegrating into civil war as a result of the Iraq war will be missed if you blink, to say nothing of the brief reference to "renditions". As Moore correctly says*,
"[The movie] has been "turned into a Bush-era parable by people too timid to set a political satire in their own country…It's a thwarted and frustrated and largely impotent American liberal fantasy of someone with American liberal values standing up against a state run by neoconservatives—which is not what the comic V for Vendetta was about. It was about fascism, it was about anarchy, it was about England."
Personally, I think the Wachowskis blew it by going for the polemic and draining the Norsefire characters of any subtlety - the only one who gets portrayed at all sympathetically is Finch, and one is never sure while watching the movie whether he's just a run of the mill Inspector or the head cop. Ah well, the movie considered on its own merits is still great fun, and the scene at the end where one sees some of the dead characters appearing in the crowd as they remove their masks is excellent.
I'm sure there's something productive I could be doing this evening, but instead I think I'm going to play something fairly mindless and then go to bed early.
*Quoted from the Wikipedia article on the comic.