Right now it seems almost as if Sarah Palin’s political action committee has one goal and one goal only: Discredit the movie “Game Change.”

Based on a book by journalists Mark Halperin and John Heilemann of the same name, the HBO film focuses on Arizona Sen. John McCain’s decision to pick Palin as his running mate in 2008. According to news reports, the film depicts Palin as unstable, unprepared and under-informed on world affairs. “Game Change” debuts March 10 on HBO.

While Palin and her aides have yet to see the movie, that fact hasn’t stopped them from relentlessly attacking the film. Two weeks ago, SarahPAC treasurer Tim Crawford told The Fix that he expected the movie to be filled with inaccuracies. Former aide Meg Stapleton called it “sick.” Palin herself told Fox News the book was “based on a false narrative.”

Now SarahPAC is out with its own trailer rebutting the film, “Game Change We Can Believe In,” saying the film “presents a history that never happened.”

Palin’s version uses clips from her 2008 convention speech along with praise from members of McCain’s team to argue that she gave the campaign a much-needed boost. In an e-mail promoting the video, her team urges HBO to label the film “fiction.”

(It’s worth noting that two of the aides featured in SarahPAC’s trailer — Steve Schmidt and Nicole Wallace — say they found the movie to be accurate.)

Why is Palin and her team so focused on badmouthing “Game Change”?

Palin has always been concerned with her public image and how she is perceived both within the Republican party and outside of it. Since she isn’t in office or running for office at the moment, her power in the public dialogue is based entirely on the perception of her prominence and influence within the Republican Party. And a big part of that reputation is built on what exactly her role was in the McCain campaign.

Palin would like to be remembered as the maverick who was too principled and independent for presidential politics, not the amateur who couldn’t cut it in the big leagues.

Palin has also always had trouble ignoring her critics, a reflexive defensiveness that has dogged her since 2008. Taking on “Game Change” may only give HBO more buzz, but she continues anyway.