Can movies change how we behave as a society? An opinion piece by Maria Dibattista in Sunday’s L.A. Times argues that they can–except for the movies that set out to do that. She adds the Oscar-nominated “Brokeback Mountain” to a lineup of “problem films” like “Gentleman’s Agreement” (anti-Semitism), “Guess Who’s Coming to Dinner” (racism), and “Wall Street” (corporate greed),which are affecting and powerful in the theater but turn out to be powderpuffs when it comes to real-world impact. “If “Brokeback Mountain” changes the way we think and act about homosexual relationships,” DiBattista writes, “that change won’t come from seeing two men throbbing with love for each other.”

From this remove, it’s difficult to gauge whether “Guess Who’s Coming to Dinner” really changed America’s attitude about race, or showed how our attitude toward race was already beginning to change. Hollywood is a generally a pretty conservative place, as any industry would be that places such large bets on what the broad audience will pay for. Officially an independent film, “Brokeback” is a major release with major stars who took the risk of sucking major face. All the principles, among them Paramount Pictures, probably felt secure in their wager that filmgoers have already accepted homosexuality. Its presence, if not its success, in other words, has probably more to do with “Will and Grace” than the bravery of the filmmakers.

So can movies change how we behave? Maybe not. But they are a good indicator of how we’ve changed already.