The Dixie Chicks have always maintained a healthy dose of rebellion. If they could just figure out what they’re rebelling against, it would serve them well.

It was during a concert at London’s Shepherd’s Bush theater in 2003 that lead singer Natalie Maines spoke for her bandmates and declared: “We’re ashamed that Bush is from Texas.”

At the time, there were widespread protests against the war, including a large anti-war demonstration in London. Ms. Maines’s words struck home, not only because she was the lead singer of a country band that counted among its fans many Bush supporters, but because she chose to make the statement in a city that was, at the time, hostile to the president and America as a whole.

In case there was any doubt about where she stood, she led into the infamous statement with these words: “Just so you know, we’re on the good side with y’all. We don’t want this war.”

Ms. Maines later issued a vague apology for disrespecting the office of the president, but she has since recanted and still seems unclear about her feelings on the situation. Earlier this year, she said: “I don’t feel he [Bush] is owed any respect whatsoever.” And upon the band’s return to Shepherd’s Bush last year, she repeated her infamous phrase verbatim.

In response to what the band sees as an innocuous statement, the Chicks were banned by country radio, subjected to scathing criticisms, and endured various protests and organized CD destruction, all of which led the group to create a musically strong and politically defiant album that earned them a cult status among opponents to the war.

But their musical rebuttal and newfound fans have not (yet) met their expectations for monetary success. And so today they are releasing “Shut Up and Sing,” a documentary that adds up to little more than a vanity project for the band, an effort to persuade viewers to translate their admiration of the band into album and concert sales.

The three women who comprise the group — Ms. Maines, fiddle player Martie Maguire, and banjo player Emily Robison — are talented and intriguing performers, but both the band and the filmmakers — Academy Award winning filmmaker Barbara Kopple and co-director Cecilia Peck — are too caught up in what they refer to as “the incident” to offer any perspective.

While some of the reactions to Ms. Maines’s statement were absurd and surely frightening for the band (culminating in a death threat to Ms. Maines), the idea that the singer’s free speech has been impinged is dubious at best.

Recording artists (and all individuals) are free to speak their minds, but they’re also free to lose business as a consequence. And the only thing proven by clips of Senator McCain taking the side of the band in a senatorial hearing is that senators are free to misunderstand the First Amendment as well.A radio conglomerate has the right to stop playing any artist at any time. (Where were all the freedom of speech crusaders when Michael Savage and Dr. Laura Schlessinger got into trouble for mouthing off?)

That said, the Dixie Chicks are a powerful force that has managed to out perform pop and country talents alike, becoming the top selling female group of all time. In trying to describe the band, the writer Chuck Klosterman once declared: “Teenage girls are the new teenage boys, which is why the Dixie Chicks are the new Van Halen, which is why country music is awesome.”

The band has managed something close to a coup in country music by mixing tradition with a decidedly rebellious streak. But despite the appeal of her passionate demeanor, Ms. Maines has no idea what she’s rebelling against, which leaves her spinning her wheels more often than not. Her habit of shooting her mouth off may get the band attention, but it has the unfortunate consequence of making her more conciliatory bandmates look like confused backup singers.There are numerous attempts in the film to broaden the scope beyond Ms. Maines and “the incident,” but most efforts to include Ms. Robison and Ms. Maguire (including a jumbled segment on in vitro fertilization) are so forced that they serve only to underscore how often the two are overlooked.

The Chicks likely warrant a full-length feature, but this sanctimonious, overly long crusade is more like an infomercial asking for a pledge of support for the Dixie Chicks. And though the Chicks are exceedingly appealing figures, it’s sometimes hard to empathize with impugned artists who have a highly successful new album and whose biggest concern is whether they’ll still be playing huge stadiums in the South (since they have no trouble doing so in Canada and most of the rest of the country).

In the aftermath of Ms. Maines’s words, the Chicks have made clear that they have no need for country fans who were displeased by their public statements.The group has been on the verge of completing their crossover from country music for a long while now. Before the “incident,” they were making the transition without cutting off old fans, but this juncture seems as good a time as any to make a break.

The Chicks hoped this decision would be rewarded financially, and it likely will be in the end, but there is also a chance they will not retain the success that they’ve had without country fans. And that’s not because their freedom of speech has been breached. The scene that elucidates this most clearly is Ms. Maines’s shock at what the president has to say about her. Asked what he thought of the controversy, Bush says: “The Dixie Chicks are free to speak their mind.They can say what they want to say. But they shouldn’t have their feelings hurt just because some people don’t want to buy their records.”

Ms. Maines subsequently responds with an eloquent: “Dumb f—!”

This isn’t remarkable because Ms. Maines still can’t stop herself from flippantly disrespecting the president on camera, or because of her language. It’s just that she still doesn’t get it. If Ms. Maines’s feelings hadn’t been hurt, she likely wouldn’t be reduced to cursing at a television screen.

Opens in New York on October 27.