In Hail, Caesar!, Joel and Ethan Coen's movie about classic Hollywood, studio fixer Eddie Mannix (Josh Brolin) finds himself in a pickle when his biggest star, Baird Whitlock (George Clooney), is kidnapped by a group of Communist writers who call themselves the Future.

“Until quite recently, our study group had a narrow focus. We focused on getting Communist content into motion pictures, always in a sub rosa way, of course,” one of the writers (Max Baker) tells Whitlock when he wakes up from being drugged. But now, they've decided to go bigger: they're hoping that the ransom they get for Whitlock can go to the Soviet Union along with Burt Gurney (Channing Tatum), a tap-dancing movie idol and secret Communist who is planning to defect.

Of course, the suitcase ends up sinking into the ocean while Gurney is boarding a submarine, Gurney himself sails off into the Soviet nightmare the writers have mistaken for utopia, the writers are arrested and Eddie Mannix gets his movie star back. Hollywood, like the house, always wins. And the writers would have done more good had they stuck to their original plan to express their ideas subtly through their movies.

In retrospect, Hail, Caesar! was the perfect kick-off for a troubled year for the relationship between pop culture and politics. As a certain brand of righteous pop culture hit grating notes and the results of the presidential election serve as a reminder that Hollywood isn't as decisive as it might seem, a certain didactic approach to influencing politics through culture seemed to find its limits in 2016.

Take Macklemore, the alternately treacly and grating rapper, who reached a new imbalance between his artistry and his intentions with White Privilege II, a seemingly unending act of self-excoriation.

Beginning with a verse about how Macklemore wonders whether he even has the right to attend a Black Lives Matter protest, the song expands to question the rapper's right to even work in his chosen medium.

Macklemore wins an award (GETTY)

In the midst of meditating on whether “it seems like we're more concerned with being called racist/Than we actually are with racism,” Macklemore unintentionally did the inverse: he spent almost nine minutes publicly worrying less about the issues than about the correctness of his stance in relation to them.

I don't doubt the sincerity of Macklemore's convictions, but White Privilege II delineated the point at which prioritising the political content of art over the quality of art's execution means that a piece fails as both art and politics.

Later in the year, Paul Feig's Ghostbusters reboot became another front in the culture wars. When the trailers first came out, internet apparatchiks went overboard scrutinising Leslie Jones' performances for traces of stereotype, and a grandstanding critic declared that he would refuse to see the movie on the grounds that redoing the original with an all-female cast was an unacceptable vandalism of a classic.

The whole meshugas escalated to the point that Jones became the subject of vicious racist and sexist attacks online.

All of which made it much more puzzling when audiences got a chance to see Ghostbusters and it turned out that the movie was a mediocre comedy with half-baked thoughts about gender.

Ghostbusters was a flop, and turning it into a feminist crusade couldn't make up for its weak plotting and minimal laughs. And though there are no circumstances in which I want to see someone like Jones be attacked the way she was, it was especially bizarre to fight what was essentially the cultural equivalent of trench warfare over a mild mediocrity. The battle, it seemed, was the point, not the movie itself.

Relative flops at the box office were accompanied by a bigger one at the ballot box. Conservatives love to complain about Hollywood support for Democrats. But it turned out that this asymmetric nature of this element of political warfare didn't matter so much.

A campaign that featured support from Katy Perry, Lady Gaga, the Clooneys, Robert DeNiro, Dustin Hoffman, Cher, Bruce Springsteen, quasi-comedic Lena Dunham videos and twee a cappella covers of Clinton's campaign song didn't outgun one featuring Antonio Sabato Jr. and Scott Baio.

If star power hasn't lost its value, then stars themselves and Democratic politicians seemed to have lost sight of how best to deploy it. Just as the writers in Hail, Caesar! overlooked their ability to change norms and shape values by making movies in favour of a silly quest to get a star to the Soviet Union, the election seemed to sap artists' influence in the very act of trying to elevate them as campaign trail surrogates.

To take a counterexample, Beyoncé Knowles-Carter's most lasting political statement of 2016 won't be the concert she headlined in support of Clinton in the waning days of the election; and it might not even be her performance at the Super Bowl, where she and her dancers took to the field of an event that's larded with patriotic symbolism in Black Panther-style berets, performing Formation, a song that's an explicit ode to blackness and female excellence; or her turn at the Country Music Association Awards, where she performed with the Dixie Chicks, who had been exiled from country music for their criticism of former president George W. Bush.

Instead, it was Lemonade itself, an album and visual experience on which country coexists with hip-hop and more traditional poetry, and that combines potent calls for liberation with the carefully calibrated tantrum that is Sorry and the seduction of Six Inch Heels.

Lemonade is an argument in favour of a version of the American experience that borrows from the best of many traditions, and a reminder that – just as former secretary of state Condoleezza Rice famously told a racist University of Denver professor “I speak French, I play Bach, I'm better in your culture than you are.” – Knowles-Carter herself excels in so many of them.

The Super Bowl and CMA performances prompted a raft of predictable political debates; Lemonade is the more expansive, and unsettling, document.

If culture is upstream of politics, 2016 is a reminder that artists should have confidence in their role. The most powerful thing they can do with their art is use it to expand and reshape the conversation, rather than shrinking and distorting themselves to fit inside the contours of a stunted political conversation – or worse, try to use that stunted political conversation to sell their art.