The targets are a mite too easy and the approach arguably too gentle in Jason Reitman’s crowd-pleasing adaptation of Christopher Buckley’s novel, but in its genial, almost gentle way “Thank You for Smoking” proves a good time. The barbs in the picture are directed against gleefully amoral lobbyists, self-important, publicity-seeking politicians, ultra-smooth Hollywood talent agents and cut-throat reporters. These aren’t exactly controversial objects of censure, and it would be hard not to hit such types at least a glancing blow. The satire here, moreover, isn’t of the sharp, edgy sort that evinces a truly nasty spirit; the movie never really goes for the jugular, preferring to be a good-natured spoof instead. But though it soft-pedals the venom and comes across more as adolescently smart-ass rather than truly abrasive, it’s still amusing.

The linchpin of the movie is Nick Naylor (Aaron Eckhart, putting his slightly seedy handsomeness and calculated affability to good use), the chief spokesman for the industry-funded Academy of Tobacco Studies, who uses his easygoing charm to deflect attacks from anti-smoking activists like Vermont Senator Ortolan Finistirre (William H. Macy, fussily funny but doing less with the part than one might have expected). Naylor loves his work perhaps too much, reveling in his ability to short-circuit attempts to impose ever more stringent controls on cigarettes and regularly comparing notes at lunch with his comrades in arms, Polly Bailey (Maria Bello, solid but unspectacular), who represents the alcohol industry, and Bobby Jay Bliss (wild-eyed David Koechner, doing a flamboyant redneck routine), the spokesman for firearms of all kinds. (The trio refer to themselves as the MODs, or Merchants of Death.)

But though his relationship with his boss (J.K. Simmons, doing much the same raging routine that he offers as Jonah Jameson in the “Spider-Man” franchise) is occasionally strained, Nick enjoys the support of The Captain (Robert Duvall, like Macy good but not exceptional), the old-time tobacco tycoon who’s the money behind the Academy. The Captain encourages him to follow up on an idea to improve tobacco’s image by having smoking be portrayed as sexy in movies again–an effort that briefly takes him to Hollywood, where he meets with accommodating agent Jeff Megall (Rob Lowe, delightfully droll) and Megall’s hilariously obsequious aide (Adam Brody, even better).

But there are problems, and not just from Finistirre. An ambitious young muckraking reporter (Katie Holmes, brittle and cold) targets Naylor for an expose, and handily seduces him for her own purposes. Nick’s young son (Cameron Bright, as dull and impassive as usual) wants to find out about his father’s job, and despite the misgivings of Naylor’s ex (Kim Dickens, practically invisible), the boy travels with his dad to California–where he meets not only Megall and his assistant but Lorne Lutch (Sam Elliott), who puts his taciturn western persona to good use as an erstwhile Marlboro Man, now stricken with cancer, whom Nick must visit to try to persuade not to attack the product he once hawked. There’s also a threat against our anti-hero from a shadowy anti-smoking terrorist group.

As is abundantly clear from all this, Buckley (who appears in a brief cameo on a subway platform) keeps his story bubbling with incident, some elements of which are more engaging than others (the reporter subplot and the father-son business never take off). And Reitman has done a fine job of translating the prose from page to screen; his script is replete with good lines, and he maintains a swift, amiable pace throughout, helped by spiffy widescreen cinematography by James Whitaker, sharp editing by Dana E. Glauberman, a sleek production design by Steve Saklad and a bouncy but not irritating score by Rolfe Kent.

Still, in watching the picture one can’t escape the feeling that it doesn’t fulfill its potential. “Thank You for Smoking” just isn’t one of the great satires–it’s too nice for that. In this day and age, however, simply touching on the kind of matters it raises makes it seem more daring than it actually is. This movie’s no “Dr. Strangelove”–it’s an even more lightweight version of “Wag the Dog.” But at least it isn’t “Dave,” or “My Fellow Americans.”