DW: You've said there is a connection between Donald Trump and motive of revenge in US cinema. One of Hollywood's most famous vigilante films, "Death Wish," happens to be one of Trump's favorites. In which context did he mention that?

Peter Vogl: During his election campaign, Trump said in a speech, while he was pressing for gun ownership rights, that he loved the film. He praised Charles Bronson and complained that the film has been categorized as politically incorrect.

In your new book, "Hollywood Justice - Selbstjustiz im amerikanischen Film 1915-2015," you examine films in which people take the law into their own hands - an issue that comes up often in American cinema. What exactly is vigilantism?

Vigilantism is a conservative, system-supporting form of self-administered justice. The vigilantes in my book aren't out for revenge and don't want to make up for a personal feeling of injustice. Rather, they carry out selfless justice in the interest of the general public. They break the law with violence in order to serve the law and the greater good.

Several aspects of your definition sound similar to Trump's worldview.

Trump does in fact bear strong similarities to the typical narrative of a vigilante film. He is a reactionary from the upper-class that uses aggressive rhetoric to put himself in the role of an outsider and says he wants to clean things up for the good of the people.

The difference is that in a vigilante film violent deeds are used instead of rhetoric, and the film hero cleans up crimes rather than the political establishment. Trump has promised to "drain the swamp" in Washington. He calls his opponents incompetent, weak and corrupt - which is exactly how the film vigilante sees the justice system he goes against.

Both are heroes for "angry white men" and offer simple solutions to complex problems. There are even more parallels…

Trump doesn't run into the street with a pistol and doesn't call for others to do that - but he does suggest that the establishment in Washington is not capable of moving the US forward and that he can take that into his own hands. Is this a kind of economic vigilantism that has also found its way into US cinema?

Trump has mentioned several times that he sometimes carries a handgun. The picture he paints is of the US being completely in the toilet and he's the only one who can lead the country to the light - like a superhero. In films, presidents have almost never been vigilantes. "Air Force One," by Wolfgang Petersen, is a better-known example. Harrison Ford plays the leader of the free world, President James Marshall, who has to liberate his airplane from Russian terrorists in action-hero fashion.

A more interesting example is "Gabriel Over the White House," which is practically unknown these days and which I discuss in my book. In the film, the newly elected president implements martial law, whips the country into shape and cracks down on criminals. It was released in 1933 when Franklin D. Roosevelt had just been elected and was introducing his New Deal to end the Great Depression. We'll have to wait and see whether Trump will issue in a caesura of similar proportions.

You list many examples from early film history. Is vigilantism one of the original themes found in US cinema? And if so, why is that?

It is actually the original theme found in American cinema. The group is weak and the individual is stronger and more effective. The hero is a loner with an unswerving sense of justice and a strict moral compass who puts himself above the law for the good and protection of his community and uses violence. The idea of regeneration through necessary violence is embedded in American history, and the American culture and psyche.

The most popular films of this genre are "Death Wish" and "Dirty Harry." What's special about these two movies?

Both are excellent action thrillers that had their finger on the pulse in the 1970s. After the hippie era and the civil rights movement, the pendulum started swinging in the other direction. The reactionary film vigilante basically comes to rescue the white middle class. He puts himself above the law in order to help the justice system which was seen as too liberal.

Is "Taxi Driver" an intellectual kind of vigilante film?

You could say that it's a more artistic vigilante film. "Taxi Driver" is a melancholy character study and, in contrast to practically all other vigilante films, it's a resigned drama, though it still has a brutal and cathartic end.

Looking back at various film eras, which pivotal developments have taken place?

In the 1930s, law-and-order films were popular. From the 1940s to the 1960s, the time of Hollywood production codes (Eds.: a set moral guidelines for films), there were only a few examples. In the 1970s, urban vigilantes that cleaned up big cities were predominant. The vigilante movies of the 1980s tend to be B films and exploitation films. The 1990s were largely peaceful and, since the 2000s, comic superheroes have made a tremendous comeback that is still going strong.

How do the "Batman" films differentiate themselves from classic vigilante films?

Batman is not only the most competent, but also the most selfless of all vigilantes. In particular in the "Dark Knight" trilogy by Christopher Nolan, he becomes a kind of Jesus figure who nearly sacrifices himself when he goes up against deterioration, corruption and anarchy to save his city. Like most vigilantes, Batman disregards out of necessity the government's monopoly on violence, but also cooperates with official representatives of the law in order to re-establish order.

Could Trump ever become a representative of the establishment who then tries to bring self-appointed avengers to justice? I mean, is the avenger - both in cultural portrayals and in reality - not always at risk of coming into the line of fire? 

It is logical that people mobilize against those who polarize in the political arena. In film, the vigilante not only bears the hate of the criminals who he fights against, but he's also a thorn in the eye of official representatives of the law who feel their authority is being undermined.

In reality, people would quickly become disenchanted with a film vigilante and the same could happen with Trump if he doesn't manage to surround himself with competent people. Trump knew how to make the most of the media landscape, in which the one who shouts the loudest and says the craziest things gets the most attention. That's true for both traditional media and social media.

When the news is turned into a 24-hour entertainment circus, you can't be surprised when a self-promoter with bold statements takes charge. Trump is a narcissist and swashbuckler who will, like all other presidents, be judged by his actions. His worst enemy could become reality and maybe then we won't need an anti-Trump as a counterpole.

Peter Vogl is the author of "Hollywood Justice - Selbstjustiz im amerikanischen Film 1915-2015" (Hollywood Justice - Vigilatism in American Film from 1915-2015).