Ideology in Hollywood? You don't have to look for it, because it always finds you. In The King's Speech the cause of the king-to-be's stuttering is precisely his inability to assume his symbolic function and identify with his title. He displays little common sense, seriously accepting that one is a king by divine will; and the task of the Australian coach is to render him stupid enough to accept his sovereignty as natural property. In the film's key scene, the coach sits on the throne. The furious king asks him how he dare do this, to which he replies: "Why not? Why should you have the right to sit on this chair and me not?" The king shouts back: "Because I am a king by divine right!" At which point the coach just nods with satisfaction; now the king believes he is a king. The film's solution is reactionary: the king is "normalised", the force of his hysterical questioning is obliterated.

The other winner at the 2011 Oscars, Black Swan, a feminine counterpart to The King's Speech, is even more reactionary. Its premise is that, while a man can dedicate himself to his mission (as in The King's Speech) and still lead a normal, private life, a woman who totally dedicates herself to her mission (here to be a ballerina) enters the path of self-destruction. It is easy to recognise in this plot the old topos of a woman torn between pursuing her artistic mission and having a happy, calm private life.

The King's Speech and Black Swan reassert the family values of the traditional couple under the masculine authority: for a man, a naive assumption of symbolic authority; for a woman, a withdrawal into privacy. But even when traditional ideology is not asserted in such a direct way, the retreat from public space into family life has a clear ideological function. Such is the case in Robert Redford's The Company You Keep, out last year, which deals with the touchy subject of leftist ex-radicals confronting their past.

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Redford plays Jim, a recent widower and single father. Jim is a former Weather Underground anti-Vietnam war militant wanted for a bank robbery and murder, who hid from the FBI for more than 30 years, posing as an attorney near New York. He becomes a fugitive when his true identity is exposed, and he must find the only person who can clear his name – his ex-lover, Mimi – before the FBI catches him. If he can't, he will lose everything, including his daughter. When Jim finds Mimi, she says she is still passionate about the goals of the Weathermen and unapologetic about her actions 30 years earlier. He tartly replies: "I didn't get tired. I grew up." Jim asks Mimi to turn herself in and confirm his alibi for the sake of his daughter.

As a reviewer put it, The Company You Keep exudes nostalgia for the time when terrorists were still people who bore recognisable Anglo-Saxon names. Nonetheless, the film captures the almost unbearably painful disappearance of the radical left from our political and ideological reality. The survivors of this movement are like sympathetic living dead, remnants of another era, strangers drifting in a strange world; no wonder Redford was attacked by conservatives for sympathy and complicity with terrorists. Where the film fails is in confronting the aspect of Weathermen activity that is most problematic: their decision to take the path of violent action.

The film acknowledges a passage from youthful enthusiasm – which can easily turn into violent fanaticism – to a mature awareness that no political cause should make us violate things like family life and responsibility towards one's children. Read this way, The Company You Keep is, as someone wrote about Neil Gordan's novel on which the film is based, le roman des illusions perdues.

However, is such a reference to growing up and family responsibility a neutral, apolitical wisdom that posits a limit to our political engagement, or is it a way for ideology to intervene? This second option amounts not to a covert attempt to justify violent terror, but to an obligation to analyse and judge it on its own terms. Without this type of radical self-examination, we end up endorsing the existing legal and political order as the frame that guarantees the stability of our private family lives. It's no wonder that The Company You Keep is about the hero's legal rehabilitation, his effort to become a normal citizen with no dark past haunting him.

Does this mean that any reference to family values should be rejected as part of ideological mystification? Emphatically no – it can also serve a radical emancipatory project, a point made in the 2009 Greek film, A Woman's Way, from director Panos Koutras. Here is the story: Yiorgos is released from prison 14 years after killing his 17-year-old brother,who was playing sex games with Yiorgos's five-year-old son, Leonidas. During his long stay in prison, he lost contact with his son, whom he now tries to trace. He spends his first night out in a cheap hotel in Athens, where he meets Strella, a young transsexual prostitute. They spend the night together and soon they fall in love, however he soon discovers that Strella is Leonidas, who has followed him from prison. She just wanted to see him, but after he made a pass at her she went along with the charade. Yiorgos runs away and breaks down, but the couple re-establishes contact and discovers that, although they cannot continue their sexual relationship, they really care for each other. The final scene takes place at a New Year celebration: Strella, her friends and Yiorgos gather at her place, with a small child that Strella is fostering. The child gives body to their love and to the deadlock of their relationship.

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Strella takes perversion to its ridiculously sublime end. Early in the film, Yiorgos traumatically discovers and accepts that the woman he desires is a transvestite. Strella simply tells Yiorgos: "I am a tranny. Do you have a problem with that?", and they go on kissing. What follows is Yiorgos's truly traumatic discovery that Strella knowingly seduced his father. His reaction is the same as when Fergus sees Dil's penis in The Crying Game: disgust, escape in panic, wandering the city unable to cope with what he has discovered. Similarly to The Crying Game, A Woman's Way depicts trauma being overcome through love; a happy family with a small son emerges.

However, the hero's discovery that his transvestite lover is his son is not the actualisation of some unconscious fantasy; his disgust is only because he is surprised by an external event. We should resist the temptation to interpret the story as father-son incest. There is nothing to interpret: the film ends with a completely normal and genuine happiness for the family. As such, it serves as a test for the advocates of Christian family values: embrace this authentic family of Yiorgos, Strella and the adopted child, or shut up about Christianity. A proper sacred family emerges at the end of the film, a family something like God the father living with Christ – the ultimate gay marriage and parental incest.

The only way to redeem Christian family values is to redefine or reframe the idea of a family to include situations like the one at the end of Strella. In short, Strella is an Ernst Lubitsch film for today, for the "trouble in paradise" when you discover that your gay lover is your son. Even if the family violates all divine prohibitions, they will always find "a small room vacant in the annex" of heaven, as the good-humoured devil says to the hero of Lubitsch's Heaven Can Wait.

• More on Slavoj Žižek

• A Pervert's Guide to Ideology is released in the UK today and on DVD on 14 October