Who is the NSA whistleblower? And why did he do what he did? A new documentary lets him speak – and film critic Owen Gleiberman is impressed by what he hears.

Citizenfour, Laura Poitras' exciting and newsworthy portrait-of-a-whistleblower documentary, is something all too rare: a movie about a seismic event that seems to take place right at the centre of the earthquake. For most of the film, we're inside the anonymous, white-walled confines of a Hong Kong hotel room in June 2013, where Edward Snowden, the former CIA system administrator, discusses his decision to leak thousands of classified documents that revealed the US National Security Agency's vast surveillance apparatus. The interview with Snowden, which takes place over eight days, is conducted by Poitras and Glenn Greenwald, the Guardian journalist who first broke the story; after a while, they’re joined by Ewan MacAskill, also of that newspaper. To borrow Woodrow Wilson's line about The Birth of a Nation, it's like seeing history written with lightning.

What makes Citizenfour riveting, as well as the most indispensable documentary of the year, is that Snowden has been a ghostly presence in this story so far. Now that we can finally see and hear him, he turns out to be an immensely thoughtful and compelling figure, an enlightened tech renegade who never wanted to be a conspiracy-thriller hero. Depending on your politics, he’s either a freedom fighter or a scoundrel, but even if you think he's the latter, it would be hard to watch Citizenfour without being a little impressed by his low-key, arrow-straight fortitude.

Snowden had followed Poitras’ work in documentaries, such as My Country, My Country, her outcry about life in Iraq under the US occupation, and he knew her name appeared on a top-priority NSA surveillance list, that meant her every move was being tracked by the agency. He figured she would be sympathetic and contacted her in a series of anonymous emails signed “citizenfour”. Early in the film, Poitras builds her status as an NSA security risk directly into the structure of the movie, flashing documents that chart her movements at airports, with the not-so-oblique suggestion that this could happen to you too. It's chillingly dramatic, a Bourne-like motif of intrigue that has the effect of making us realise that no, this is not just a movie.

Snowden, who turned 30 when Citizenfour was shot, is far from a radical rabble-rouser. He was raised in a military family, and in his designer glasses and T-shirts, thatchy hair, and young man's stubbly goatee, he looks like a hip young college professor.  And he is clearly scared: when Citizenfour was filmed, he was living with the awareness that he would probably be sent to prison, and this charges everything he says with paranoid meaning. Snowden wears his potential martyrdom modestly. He comes across as a desperate citizen who has grasped, with creeping dismay, that the NSA  reacted to 9/11 by amassing records of every phone call, e-mail message, and data search made in the US. Under the presidency of George W Bush and then Barack Obama, the organisation became a kind of surveillance vacuum cleaner, disregarding the very concept of privacy as a means to stop terror. By comparison, the days when the CIA would spy on people by sticking a recording device in a lamp seem nearly medieval.

Poitras is a skillful yet rather prosaic filmmaker. Citizenfour has a few true-life suspense moments, like the scene in which Snowden nervously responds to each phone call to his hotel room as through his cover were about to be blown. In the end, there isn’t that much to the movie apart from what Snowden has to say. Fortunately, that proves to be enough. Even if the NSA’s motives were defensible, Snowden perceived that with the new, omnipresent data-gathering system in place, the American government had pushed past the boundaries of acceptable conduct– that given the wrong leader, the country could begin a slide into despotism. That’s why, once he perceived the scale of the NSA’s actions, Snowden felt he had to reveal what he knew. He saw it as his duty: America's new system of mass snooping was itself a secret that had to be revealed.

But there’s a contradiction at the heart of Citizenfour. At one point, as the story is breaking, Snowden makes the observation that it would be a grave mistake if he became the story. That, he claims, would take the focus off the NSA. He's right, of course. And by going underground before being granted asylum in Russia, Snowden was able to avoid the limelight. But that's not the case in Citizenfour. The film offers nothing new in the way of information about America's octopus-armed surveillance state. What's new in the film is Edward Snowden's personality. And though that’s obviously a vital dimension of the story, watching Citizenfour, we're so caught up in the drama of Snowden’s presence that it's hard to say if he ultimately advances the issue of NSA surveillance or turns it, in effect, into a form of personality journalism. The film raises the question: is the NSA something that people would even care about without a poster boy? One desperately wants the answer to be yes. But the news-junkie high of seeing Snowden in Citizenfour makes you wonder if the answer may ultimately be no.

★★★★☆

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