Joaquin Phoenix stars as the Joker in the new Warner Bros movie. Photo / supplied
Joaquin Phoenix stars as the Joker in the new Warner Bros movie. Photo / supplied
It is well known that the Ku Klux Klan was founded in the aftermath of the American Civil War, but rather less so that within a few years it had all but fizzled out.
By the time it had been classified as a terrorist organisation by the federal government in 1870, the white supremacist group had already been formally disbanded, and it was soon a more or less spent cultural force. What brought it roaring back to life more than 40 years later was a film.
The Birth of a Nation, a historical epic directed by DW Griffith, was released in US cinemas in February 1915. Often described as the first blockbuster, it was an immediate hit. Adapted from a novel called The Clansman by Thomas Dixon Jr, a Southern Baptist minister, it painted the Klan as the saviours of true white American culture, and the country's newly emancipated black population as sexually predatory, brutish and treacherous.
And lo and behold, that same year the Klan was refounded - with a fury and momentum its previous incarnation had lacked. The new version drew inspiration from Griffith's film: not just the peaked white hoods and burning crosses, but also a new fixation on protecting "the sanctity of the home and the chastity of womanhood".
By 1924, the Klan's membership stood between four and six million - cinema had proven to be one heck of a recruiting tool.
One century later, are we still so susceptible? That question is being nervously asked in light of Joker, a new Warner Bros film which transplants the classic Batman antagonist into a sickeningly familiar social context.
Played by Joaquin Phoenix, the villainous clown is here reimagined as a seething recluse called Arthur Fleck - a wannabe stand-up comedian willing to go to murderous extremes to be noticed by society at large.
Joker is set in the early Eighties, and has been heavily influenced by Martin Scorsese's Taxi Driver and The King of Comedy - arguably the two New Hollywood urtexts of urban male alienation.
But Arthur's plight also recalls a very modern dark phenomenon: the incel (or involuntary celibate) internet subculture, a racist and misogynist hate movement which has been linked to recent mass shootings in California, Texas and New Zealand.
When I first saw the film that resonance made me uncomfortable. The new Joker is hardly held up as a hero, but there is a blood-curdling glamour to the character's journey from downtrodden nobody to the extolled figurehead of an anarchist movement.
Might the film end up inspiring the very kind of violence it depicts? It's a thorny question, and when I put it to Phoenix in an interview he walked out of the room. But others are clearly aware that it might.
Earlier this week, the US Army confirmed it had issued a warning to servicemen and women about potential mass shootings at Joker screenings, and in Aurora, Colorado, relatives of the victims of the 2012 shooting at a screening of The Dark Knight Rises, another Batman-related film, wrote to Warner Bros to express concern over its content.
To be clear, no film can hypnotise ordinary cinemagoers into violence. But for the already disaffected and disturbed, history has shown they can serve as both a catalyst and template.
Taxi Driver itself was a factor in the attempted assassination of President Ronald Reagan in 1981: the gunman was obsessed with the film, in which Robert De Niro's character plots the shooting of a presidential candidate.
Oliver Stone's violent Bonnie and Clyde-style thriller, Natural Born Killers, inspired a series of copycat crimes, including the 1999 mass shooting at Columbine High School.And in 2009, 17-year-old Kyle Shaw, who bombed a New York City branch of Starbucks - with no casualties, mercifully - told investigators he was trying to launch his own "Project Mayhem", the terror movement led by Brad Pitt's character in Fight Club.
In the early Seventies, such was the furore over a spate of crimes that resembled some of the violent sequences in Stanley Kubrick's A Clockwork Orange that Kubrick himself had the film withdrawn from UK cinemas in 1973.
Yet in an interview with Sight & Sound a year earlier, he cast doubt on the causal relationship, saying: "To try and fasten any responsibility on art as the cause of life seems to me to put the case the wrong way around."For Joker too, Kubrick's words ring balefully true.
When cinema feels dangerous, it is often because it reflects a real-world danger that we might prefer was out of sight and mind. It is less as a symptom of societal sickness than a diagnosis. And we ignore the doctor's orders at our peril.
