Nowadays, you can throw a dart at a newspaper movie listing and hit a film with some post-Sept. 11 import. But, while 2005’s Batman Begins was director Christopher Nolan’s indictment of society’s fear of terrorism, its sequel is a nuanced, occasionally convoluted examination of the consequences of the Bush Doctrine.

The Batman (Christian Bale, again) we meet in The Dark Knight is regarded both as a savior and reviled as a vigilante. Moreover, he has embraced the mantle of preeminent superpower, indulging in variant forms of wiretapping and bounty hunting. This superhero believes that the end justifies the means.

Enter The Joker (Heath Ledger), a homicidal psychotic who trains his sights not so much on the Caped Crusader as much as newly appointed District Attorney Harvey Dent (Aaron Eckhart). Indeed, Dent is Gotham’s white knight, embodying an (American) ideal that Joker strips of his innocence and deforms into a conflicted, savage husk who jettisons his principles for the sake of vengeance against foes both real and collateral.

While terrific, The Dark Knight is not the masterpiece many would proclaim. The storyline is at times bloated and meandering as director Nolan tries to squeeze too much into an overlong 2 1/2-hour running time. However, Ledger’s performance is so mesmerizing that it transcends the real-life tragedy surrounding his final bow: He emotes equal parts menace, humor, eeriness, melancholy and even charisma. And Nolan’s visual aplomb and expert action sequences are tremendous, especially in the IMAX version, which includes several minutes of footage filmed using special IMAX cameras.

At the core of the zeitgeist allegory is the realization that the way to win the war on terror is not just brute force but also robbingeven by self-sacrificeyour opponents of the grandeur they crave. Stripped of their masks of evil, they all just look like a bunch of crazy jokers.