Towards the end of Desiree Akhavan’s incendiary sophomore feature, The Miseducation of Cameron Post, Chloë Grace Moretz’s central character attacks the anti-LGBT Christians running the conversion therapy camp where she is living for the emotional abuse inherent in “programming people to hate themselves”. She has spent months encased in the world of the God’s Promise camp, in which homosexuality is euphemistically referred to as “SSA” (same-sex attraction) and the residents are called “disciples”. Akhavan’s film is an angry depiction of a Christianity that is openly hostile to anyone whose sexuality sits contrary to the notion of the traditional nuclear family and, with that, it joins the ranks of a 2018 movie canon that positions religion squarely as an antagonist.

At the beginning of the year, Greta Gerwig’s Lady Bird focused on the title character’s struggles at a Catholic school in 2002. The structures and prejudices of that environment fuel her disdain for her hometown and her sense of rebellion against a world in which the refrain of “six inches for the Holy Spirit” separates amorous couples at a high school dance. For 35-year-old Gerwig and 34-year-old Akhavan, these stories hark back to their own days of youthful fightback in the 90s and 2000s. A new generation of film-makers are turning their eyes, and their poisonous pens, against the prejudices of their earlier lives – prejudices fuelled by religion.

Moving drama ... Molly Wright in Apostasy. Photograph: Curzon Films

Britain has its own analogue to this duo in Manchester-born auteur Daniel Kokotajlo. He made his feature debut this year with Apostasy – a tale inspired by his own upbringing as a Jehovah’s Witness. It’s a moving story that sees a family of three torn apart by the fundamentalist restrictions of their religion, with one daughter “disfellowshipped” when she becomes pregnant by her college boyfriend, and the other struggling with the Damocletian peril of a dormant blood disorder that could kill her if she follows the church’s doctrine and refuses a transfusion.

Apostasy, perhaps by virtue of its director’s background, is a more even-handed depiction of religion than either Cameron Post or Lady Bird. The faith of the Witnesses is not positioned as irrational, but is clearly marked as antagonistic, with the patriarchal leadership ruling that mother Ivanna – played with heartbreaking tenderness by Siobhan Finneran – can have only minimal contact with her daughter and granddaughter. With Ian McEwan adaptation The Children Act arriving in cinemas last week, it’s the second film of the year to focus on the strict orthodoxy of Jehovah’s Witnesses when it comes to blood.

That religious double standard – promising love and protection while pushing away those who don’t have absolute faith – is also at the forefront of Paul Schrader’s First Reformed. Developing its “male loner on a moral crusade” themes from Schrader’s own script for Taxi Driver, it’s a movie that sees Ethan Hawke as a reverend whose increased awareness of eco-activist concerns leads to a crisis in his faith, particularly when he discovers his historic church’s parent organisation takes large amounts of money from an environmentally sketchy energy company. Schrader evokes the uneasy dynamic between religion, money and power in a way that casts the reverend as a self-destructive avenger figure, right up until the finale.

Loner on a moral crusade ... Ethan Hawke in First Reformed. Photograph: Allstar/Killer Films

That uneasy power dynamic brings it back to The Miseducation of Cameron Post. When Moretz’s title character takes her stand, it’s because the teachings and pressures imposed by God’s Promise have led to something horrific happening to one of the camp’s residents. This camp is a world from which it is seemingly impossible to escape, as those with power over these children – their parents, schools, etc – are complicit in sending them to be “fixed” and changed in the name of the norms imposed by their religions. The Jehovah’s Witness characters in Apostasy, and the students of the Catholic school in Lady Bird, would be able to sympathise with that.

All of these films feel particularly vital given the prominence of religious values in political regimes on both sides of the Atlantic. In America, Donald Trump’s most polemic rhetoric has a quasi-religious feel and his administration publicly sided with the Christian baker Jack Phillips, who refused to bake a custom wedding cake for a gay couple. In Britain, Theresa May’s father was a vicar and her Christianity is something she has never shied away from in her political career. She used her most recent Christmas message to declare that the UK should “take pride in our Christian heritage” and defend the “values” of the faith.

Against this backdrop, these movies serve as a fervent, rage-filled counterpoint from liberal film-makers to the rightwing rhetoric, fuelled by religion, that is dominant in western politics in 2018 – despite increasingly secular societies. For a whole generation of young directors – and at least one renowned veteran in Schrader – the biggest movie bogeyman of 2018 is the power of fundamentalist religion.