We have seen these images before. People running from a public place; and hundreds of policemen and security forces taking over a building (this times a movie theatre and the house of the killer). And then the candles, the US flags, people crying and embracing each other, the politicians and President´s condolences. In the following days we will read the articles and commentators in the media deciphering the psychology of the assassin. And then, oblivion, particularly for the voices that have raised the issue of gun control in a country where there is barely any control at all, legislation primarily depends on individual states, and an unknown person with mental troubles can order any kind of arsenal over the internet.

This time the assassin made his move during the Presidential campaign, killing 12 people and wounding nearly 60, and putting the incumbent President and the leading opposition candidate on the spot. But both have been reluctant to condemn forthrightly the National Rifle Association’s liberal interpretation of the controversial Second Amendment to the US Constitution. Gun enthusiasts maintain that it allows individual private citizens to possess firearms in the home; in addition, many on the US right feel that these weapons are necessary to defend themselves from an overbearing and intrusive state.

While this silence about an antiquated principle in a modern and democratic society is odd and shameful, there is another problem that the authorities in the US (and in most of the world’s societies) avoid addressing: the culture (or subculture) of violence in the electronic entertainment era.

Tens of thousands of books, essays and articles have been produced in recent decades about violence in the entertainment media business, at least since the 60s when television became part of the family´s living rooms and the film industry became more challenging about explicit violence. And thousands of reports have been prepared by experts about the impact that violence has on media messages, particularly those focused on young people. And after every occasion of mass murder this link has been stressed—to no avail.

This relationship between violence and the media messages not only affects mentally disturbed people in the US or Finland (to mention two countries with limited gun control) but also has offered a model of perverse conduct to sadistic militias from the Balkans to Liberia, Sierra Leona and the Democratic Republic of Congo.

For the media moguls and the people who benefit from the distribution of film-TV-video games, making the link between fictional violent messages and violent behaviours is a crude oversimplification. Like the National Rifle Association, the beneficiaries of the violent media business quickly raise the flag of individual liberties, even the freedom to be an assassin. Neither the weapons nor the media messages, they say, kill people but mentally ill individuals – who make the wrong use of entertainment or legitimate tools of defence.

But as the French essayist Régis Debray once wrote in the 1990s, “one ends up looking like what one reads, and now, what one sees. To live is to tell stories. Just four days ago the stories were on paper, yesterday they were on celluloid, and now they are in electronic form. Depending on whether a young man sees Easy Rider or To Die in Madrid, Battleship Potemkin or Citizen Kane, his destiny will change. The image rules our dreams, and the dreams, our actions”. Debray was debating with writer Mario Vargas Llosa the need to protect the European cinema from US blackbusters. This problem today is aggravated because technologically we have moved on from TV and cinema to video-games, free internet access to violent content, and the individual capacity eventually to film or snap with a cell-phone’s digital camera the cruellest images, in some cases engineered by ourselves.

A few years ago a group of young men burned and killed a beggar in Barcelona and filmed their adventure on their cell phones. In the Abu Ghraib prison a series of US Army guards photographed the prisoners, including the corpses of some victims of torture, creating a worldwide show of shame that the late Susan Sontag labelled "the US pornography of violence", indicating that a part of US society was immersed in it.

This time in Aurora the killer has been dramatically obvious. He tried to imitate the character of the Joker, who in the first two parts of this Batman series, kills people for the sake of killing them. He dyed his hair, bought an arsenal, prepared booby traps in his flat for “Gotham´s” police and went to the theatre to match the fictional Joker (Bane in this film) and take on Batman in combat as in “The Dark Knight Rises”, confusing fiction and reality.

The confusion was aggravated by a film industry that had organized a massive global event. For the assassin it created the perfect showtime environment. The distribution company prepared events around the world for the Batman film, from Paris to New York. It would be impossible to blame the entertainment industry for promoting its products, although there is something obscene in the fact that in the first weekend after the massacre, the film had raised 180 US million dollars just in the United States. This time the Joker won his game with Batman.

The distance is very short between the Aurora killer and the soldiers in Abu Ghraib taking pictures of naked Muslim prisoners after torturing them, the teenage soldiers wearing Rambo attires in Sierra Leone, the man that tried to kill a US Congresswoman in 2011, the man that a year ago killed 77 people in Norway to protect his country from Islam, or the militias on the border between Arizona and Mexico that wear military dress to capture illegal immigrants.

For sure they are all people with disturbed minds, but supported by extremist ideologies and encouraged and mobilized by entertainment products that constantly cross the line between fiction and reality. If the testimony of Anders Behring Breivik is of any use, he declared that in the years before massacring 77 mostly young Norwegians, he trained himself by playing violent video games for hours in order to “dehumanize” himself.

It seems to be an old fashioned idea, but we are a product of the contexts in which we live. In the same way that Rupert Murdoch´s empire and actions are now under investigation, the time has come to regulate violence in the entertainment world.