Don Cheadle, heart sewn to his sleeve, is badly miscast in this war-on-terror thriller — not for a moment did I believe that his gentle, soulful character had the stuff to function as a serial mass murderer, let alone gain the confidence of other cold-blooded killers. Nonetheless, this film is populated by radical jihadists who trust this American expatriate with the execution of the most elaborate paranoid fantasist’s orange-alert wet dream of a terror attack on U.S. soil. Cheadle is a cool enough character that this wouldn’t necessarily be a deal-breaker, but the transparency of his intentions renders the film’s coy guessing games about his allegiance more or less redundant. Writer/director Jeffrey Nachmanoff’s previous big-ticket screen credit is the screenplay for The Day After Tomorrow, and though his model for Traitor is obviously something like Syriana crossed with The Departed, what he’s come up with here is about as subtle as a Roland Emmerich film. His script strives to be even-handed in its representation of terrorists, who are depicted as thoughtful and well-spoken enough that a disaffected, revenge-minded American could fall in with them, but the unremittingly pointed dialogue betrays the characters’ two-dimensionality. (They’re most credible when they’re not talking.) Guy Pearce is quite good as the agent who suspects that Cheadle might not be the international sociopath the rest of the FBI has him pegged as, but the film isn’t as clever as it needs to be to drive the cat-and-mouse storyline. By the time Cheadle’s character makes the biggest chump move in the book — visiting his ex-girlfriend in Chicago even though any terror plotter worth his C4 would know she’s under surveillance — Traitor has proven itself to be about as realistic as any given episode of 24, but not half as much fun. C