M is the greatest movie ever made about 9/11 and the “war on terror.”

M, which made German actor Peter Lorre into a major film star, and which director Fritz Lang considered his masterpiece, says just about everything there is to say about a corrupt society’s response to an unspeakable atrocity. The Sandy Hook Massacre, the Boston Marathon bombing, Roman Polanski and Wood Allen, our media treats each new crime wave, each new shocking act of violence, each new opportunity for the authoritarian state to increase its hold over the people, as a break with history, as a loss of American innocence. Yet, as Lang demonstrated all the way back in 1931, it is a pattern is probably an intrinsic part of the capitalist metropolis (pun certainly intended).

M opens in a courtyard in Berlin. We look down from the balcony onto a group of children, who are playing a game called “elimination.” They are singing a song about the bogeyman, a child murderer based on Peter Kürten, the “Vampire of Düsseldorf.” A woman comes by to tell them to “stop singing that horrible song.” Unlike these innocent children, she knows that there’s a real child murderer on the prowl in Berlin. Her neighbor, Frau Beckmann, tells her not to be uptight. Let the children sing. They’re not bothering anybody.

Frau Beckmann’s daughter Elsie becomes the serial killer’s next victim.

The American film industry has produced hundreds of films about monsters of all kinds. We should be completely desensitized by now, but the opening of M is still chilling. Elsie, a little girl with tangled golden hair, dashes out of the school yard into the street. She comes close to getting hit by a car, but an alert police officer pulls her back. Then she looks at a poster on a kiosk. She reads. A child murderer is on the loose. A shadow looms over Elsie on the kiosk.

Hans Beckert, Peter Lorre, who’s probably best remembered for his cameo as a terrified little man on the run from the Nazis in Casablanca, is a short, pudgy, round face little man with greasy hair and a pale, nervous stare. He’s the kind of nonentity most of us would brush by on the subway without a second thought. Elsie is no more afraid of him than we would be. He buys her a balloon from a blind beggar (a man who will later be a key figure in the plot’s resolution). He whistles “In the Hall of the Mountain King” by Edvard Grieg. They walk off together. We know Elsie is doomed. We flash back to her mother. Elsie hasn’t come home with her friends. At first she thinks nothing of it. Then she begins to worry. Then she descends into a white knuckled panic. The next day the balloon has floated away and gotten itself caught in a cluster of power lines. What happened to Elsie? Newspaper hawkers pour out into the streets with the horrible news. There’s been another child murder. The victim’s name was Elsie Beckmann.

What happens next will surprise nobody who was tuned into American television during the aftermath of the Boston Marathon bombing. The Berlin police lock down the whole city. Uniformed gendarmes pile into trucks and spread out, neighborhood by neighborhood, block by block. The problem is they have no idea who they’re looking for. The child murderer isn’t a pimp or a safe cracker, a burglar or a stickup man. He doesn’t have to fence stolen goods. He doesn’t have to maintain a presence in the city’s red light district.  He finds his victims purely by chance, dumps the body, then disappears back into the shadows. He could be anybody.

There’s another group of people who are under even more pressure than the police, or even the city’s parents, to bring the monster to justice, criminals. The social order of Berlin, like any big capitalist city in the 1930s, depended on an unspoken but well-understood balance of power. Capitalism produces inequality. Inequality means crime. Criminals eventually organize themselves. In the 1930s, in Chicago, in Southern Italy, in Berlin, organized crime developed a hierarchy that became, in effect, the mirror image of the state. Criminals understand the police. The police understand criminals. The child murderer, however, becomes a wild card, the “joker,” to use a contemporary American example, a source of chaos that threatens to undermine the social order altogether. Suddenly, hookers can’t find clients. Saloons lose money. Pickpockets find themselves waiting in line to show their, non-existent, papers, and getting carted off to jail when they can’t. The city’s crime bosses come together to discuss a solution to the problem. Their meetings in a dark, smoke filled room look so much like the simultaneous and parallel meetings of their counterparts in the homicide bureau that there’s no possible way a master filmmaker like Fritz Lang could not have meant it intentionally. The police and criminals are two sides of the same coin, codependent power brokers who depend on each other for their existence.

The criminals are also much better at detective work than the police. They organize the homeless, who fan out over the city and shadow any grown man they notice with a child. False accusations are made, bogus leads pursued, but, eventually, Hans Beckert slithers back onto the scene to hunt for his next victim. What proves to be Beckert’s undoing is his chosen method of bribing children with balloons. He holds hands with a little girl. He whistles his trademark tune from In the Hall of the Mountain King. It’s the same balloon vendor who unknowingly witnessed him abduct Elsie Beckmann. This time the blind man notices. As the dragnet is woven around the monster, the rope strung around his neck, Becket more and more begins to resemble, not a man, but a hunted animal. Finally, he’s caught.

Why did Adam Lanza slaughter 25 grade school kids? Why do pedophiles molest children? What is the source of evil? Is it original sin? Is it social inequality? After Hans Beckert is hauled up in front of a kangaroo court full of petty thieves, prostitutes and crime bosses, he confesses his crimes. He’s the child murderer. He did it. Why? He doesn’t know. It’s an urge he can’t control, an urge so powerful he blacks out and forgets what he’s doing even as he’s committing his monstrous crimes. Is it the desire for oblivion? Certainly not. Beckert is not defiant. He clings to his existence with the desperation of a cornered animal. He doesn’t want to die. When the police raid the underworld court and drag him off to a real jail, he whimpers pathetically. He’s relieved, grateful. He’ll get a few more weeks of life before the state sentences him to death.

If M had difficulty getting a distributor in Nazi Germany its easy to see why. There’s no direct allusion to fascism in M, but Fritz Lang is raising questions that get to the bottom of how the social order should be maintained. Pests like Hans Beckert exist. They need to be snuffed out or isolated from the rest of humanity. But who gets to judge who lives or dies? Lang is extraordinarily and, as it turns out, prophetically dour and pessimistic about the administration of justice. If there’s very little difference in M between the criminals and the police, between polite society and the underworld, any distinction that existed at all would collapse in Germany only a year later. Pests like Becket would soon hold state power. The nihilist urge that compelled him to kill children would soon engulf all of Europe.