The controversies aroused by Abdellatif Kechiche’s new film, “Blue Is the Warmest Color,” show just how hung up on sex Americans are, left and right—and why, to a certain extent, they’re right to be hung up on sex, even while drawing the wrong conclusions. The movie has proven controversial in a variety of ways (unfolded here by my colleague Emily Greenhouse), but all the debate would have slipped away into footnotes of the classic “tortured genius” genre if not for the three long, explicit sex scenes. Those are what sparked criticism from Julie Maroh, the author of the graphic novel from which the film was adapted, for “the director’s visual bias,” and from Manohla Dargis, of the Times, who likens Kechiche’s filming to pornography. The scenes have led to the film being banned in Idaho and to an NC-17 rating that the IFC Center in New York is defying—to the outrage of the Parents Television Council, which is threatening to make it a “national issue.”

The film’s two lead actresses, Adèle Exarchopoulos and Léa Seydoux—who were jointly awarded the Palme d’Or at the Cannes Film Festival along with Kechiche—spoke of the scenes, with Seydoux calling them “very embarrassing” and Exarchopoulos saying as much in different terms. Exarchopoulos—who plays the title character (the French title translates to “The Life of Adèle, Chapters 1 and 2”)—later addressed the excessive attention paid to the twenty minutes of sex in the three-hour movie:

I understand it. American audiences aren’t used to it. It’s a choice by the director. We all have sex, it’s like a drug, everyone loves it. We had to show how making love to someone is visceral. We had to convey how much of yourself you give over. So we chose to show to everyone the emotion behind the discovering of one’s sexuality. We are adults, so come on. It’s fiction, it’s cinema. I don’t get the big deal.

Exarchopoulos’s conflicted feelings get to the heart of the matter: sex is actually never not a big deal, whether in movies or in life. Sex is the joker in the deck, the infinite variable that provokes, on screen as in life, radically divergent and wildly unpredictable responses and consequences. But Kechiche brought trouble on himself—not by the decision to film sex scenes between two women but by the audacity of his artistry in doing so. The problem with Kechiche’s scenes is that they’re too good—too unusual, too challenging, too original—to be assimilated (despite Dargis’s protests to the contrary) to the familiar moviegoing experience. Their duration alone is exceptional, as is their emphasis on the physical struggle, the passionate and uninhibited athleticism of sex, the profound marking of the characters’ souls by their sexual relationship.

Most sex scenes in movies are index-card signifiers, giving visual evidence of the fact that the characters have sex at a given point in the story but not actually showing much of significance about the sexual relationship. Thus—to pick an example now on screens—the banal sex scenes between the characters played by Vincent Lindon and Chiara Mastroianni in Claire Denis’s “Bastards.” Had Kechiche limited himself to quick scenes featuring the long-familiar pneumatic conventions of writhing and sighing, there would be little embarrassment and little debate. But, rather, he gave the sex scenes between Adèle (Exarchopoulos) and Emma (Seydoux) a roiling power and an emotional weight that are central to the story. The scenes are rough, tender, funny, and harshly searching—each of the characters gives thoroughly, exhaustingly of herself as she seeks, as if in severe and sincere questioning, what she can discover from the other.

I’ve written a few occasions about the intrinsic danger of filming sex—for actors and for directors—and I’m immensely sympathetic to Exarchopoulos and Seydoux for the terrifyingly vulnerable performances they give in the film, and, above all, in those sex scenes. The scenes aren’t technical—Kechiche isn’t after a catalogue of lesbian sexual practices and pleasures—but emotional, and they capture the very vulnerability, the uninhibited, un-self-sparing exertion to exhaustion that marks the actors’ performances. At the very least, the movie reflects what the actors gave—even if they gave more than they ever expected to give, and perhaps more than any actor should ever be asked to give.

The difference between the sex scenes in “Blue Is the Warmest Color” and those in, say, “Last Tango in Paris” is that Kechiche gives the impression of working (almost) as hard as his actors do. The young Bernardo Bertolucci made a supremely great movie, thanks to his actors, who bared their bodies and their souls in the presence of a director who seems not to have recognized the gravity of what he was asking of them.

Kechiche, by contrast, directs with a sense of fervent urgency; he gives the impression of having driven himself with as much self-sacrificing energy as the actresses unleash. But there is nonetheless an intrinsic difference, even an incommensurable gulf between the performance on camera of scenes of such deep and volatile intimacy and the filming of them from behind the camera.

The superb movie doesn’t deserve to be the object of opprobrium from all sides; but the controversy that the movie has sparked is, in effect, the abyss that the director and the actors, in rising to the challenge of dramatizing sex, fell into. As engaged and soulful as Exarchopoulos and Seydoux’s performances are, it can’t be easy for them to have done what they did and to be seen worldwide doing it (and the swing in Exarchopoulos’s remarks from inhibition to bravado, from embarrassment to pride, is as much a sign of the difficulty as is Seydoux’s outright resentment). In retrospect, the turn of events should be no surprise. In fact, it’s how things should be. Society at large, in its blind and blundering way, senses that sex is perhaps the biggest deal of all, and, if the director and the actresses were ever in danger of forgetting it, the media noise will remind them as they clamber back up.

P.S. Kechiche is in the news today, speaking against the French system of state financing of movies, which, he says, makes the “authentic producer hardly exist any more in France.”

In the United States, the cinema is considered an industry, it is independent of the state and the producers know that they need an auteur cinema, its creativity, its novelty, they finance it and take the risks in financing it because they know … that a great work may be born of that cinema.

He adds that he does know a few French producers who “are ready to ruin themselves to make films” and speaks of his producers from the company Wild Bunch, “who love the cinema and take risks to make films.” His perspective on risks and personal relationships in the making of movies behind the scenes is consistent with his work on the set and with the results he gets on the screen. (Last year, Vincent Maraval, that company’s founder, sparked debate on the French system of movie financing; I wrote about his remarks as they relate to the over-all problems of subsidy.)