On February 29, 2004, Errol Morris lumbered up the steps of the Kodak Theatre in Los Angeles, to accept the Academy Award for Best Documentary Feature for The Fog of War. The film traced the life and times of former secretary of Defense Robert McNamara, including over 20 hours of interviews between Morris and McNamara in which the latter ultimately admits that the Vietnam War was a mistake.

“Forty years ago this country went down a rabbit hole in Vietnam, and millions died,” said Morris during his acceptance speech. “I fear we're going down a rabbit hole once again. And if people can stop and think and reflect on some of the ideas and issues in this movie, perhaps I've done some damn good here.”

Two months later, the controversial First Battle of Fallujah—or Operation Vigilant Resolve, as it’s known—took place, in which U.S. military forces aimed to capture the city of Fallujah in response to a rash of killings.

Ten years after The Fog of War, Morris is back with his latest documentary, The Unknown Known. This time Morris sat down with Donald Rumsfeld for over 33 hours of interviews to discuss his career and much-maligned tenure as secretary of Defense under President George W. Bush, which ended in his resignation. To grill Rumsfeld, Morris used his “Interrotron” device, which, for the uninitiated, is a teleprompter-like setup where both Morris and his subject are staring into separate video cameras facing them, but see the other person’s face displayed in the camera, so the subject is speaking to Morris, but staring directly into the camera.

The bulk of The Unknown Known sees Rumsfeld reading damning memos he fired off during his tenure as Defense secretary. He sent over 20,000 of these memos—or “snowflakes,” as he calls them—during his six years in office. It is an especially timely documentary given that we're on the verge of attacking Syria, and Rumsfeld has spoken out against intervention there.

THE DAILY BEAST: How the hell did you get Rumsfeld to agree to do this? Were you chasing him down?

ERROL MORRIS: No, not at all. I wrote him a letter, enclosed a copy of The Fog of War, heard back from him very quickly, went to Washington, and spent a good part of the day with him. We started it under the premise that he would do two days of interviews, I would edit it, and if he liked it, we’d sign a contract and continue. If he didn’t, I’d put the footage in a closet, and it would never see the light of day.

Did you go into this thinking that Rumsfeld had basically taken the fall for many of the Bush administration’s failings, so you thought he’d break down a little easier than he did?

Well, he didn’t break down at all. But I don’t go into stuff with that presumption. I go in with the idea that I might learn something. He’s a mystery to me, and in many ways, he remains a mystery to me—except for the possibility that there might not be a mystery. Does he believe what he says? He well might believe what he says.

A lot of people are going to go into this film thinking, Errol is going to break Rumsfeld the same way he broke McNamara.

I didn’t break McNamara. McNamara broke himself.

But it was your interrogating, too.

You know, I like to think I create a situation where people can talk and want to reveal things to me. I don’t know what questions I’m going to ask specifically, or the order I’m going to ask them. I’m endlessly surprised by what I hear in an interview. When Rumsfeld starts explaining to me how there was no way that the policies of Guantánamo could have migrated to Afghanistan and Iraq, and then I read him this relevant passage from the Schlesinger Report, where Schlesinger, the secretary of Defense [Rumsfeld] replaced in the Ford administration, says they did migrate, when I read it to him, Rumsfeld looks at me and goes, “Well, I’d agree with that.” What?! Huh?!

That’s a great scene. Of all the so-called nefarious characters within the George W. Bush administration, why Rumsfeld?

If I’m asked to think about the two major secretaries of Defense of the last 50 years, it’s Robert S. McNamara and Donald Rumsfeld—two secretaries of Defense who presided over disastrous wars and were major public figures. People are going to say this is The Fog of War 2. One very big difference between [McNamara and Rumsfeld] is that McNamara says the war was a mistake; it was wrong. He didn’t say it at the time, but has subsequently said it. Rumsfeld? Not so much. I always say it’s Tabloid 2.

Why Tabloid 2?

It’s really about a person who has no conception of themselves—or reality.

That really comes through in the documentary, that Rumsfeld is a fantasist who has this bizarre obsession with nebulous philosophical quotes, as revealed through his memos, or “snowflakes.”

There’s something extraordinarily—to me—interesting about him as a character, and about the “snowflakes.” I was just talking about the things journalists will say about my film, which I dread, one of which is, “There’s nothing new here. We’ve heard all of this before.” Not true. Those memos are being revealed for the first time, and there’s a lot of incredible stuff in those memos. This idea that Saddam has crawled a good way out of the box, and we may have to confront a Saddam armed with nuclear weapons—essentially the justifications for regime change and taking out a couple of additional countries, which he says explicitly. And he goes on and on and on. It’s so strange.

The title comes from one of his more difficult “snowflakes” to interpret.

But on some simple level, he’s really describing himself: the unknown known. It’s this whole idea, which I find fascinating, that the unknown unknown, the only way you can deal with it is by imagining what might happen, followed by this memo to the president of the United States saying, “The absence of evidence isn’t evidence of absence.” Wait a second ... You can justify anything that way! There are no limits! Later, because we had notes back and forth of corrections he wanted made, he said, “It really should be that ‘absence of evidence isn’t evidence of absence OR evidence of presence.’” And I wrote back to him, “OK, but that’s not what you wrote to the President of the United States. That additional clause was NOT IN THE MEMO!”

Did you take any of his corrections into account?

I took them into account if I felt that he was right. If I didn’t, I did not. I was not under any contractual compulsion to take any of the comments.

What were some other parts of the documentary that he took issue with?

I’m gonna see if we can publish all of them, but he said I should make it clear that the policies of the Bush administration were just a continuation of the policies of the Clinton administration, and I said, “I can’t do that because, reading your own memo, you’re saying that [Saddam] has crawled a good way out of the box, and ‘the box’ is the no-fly zones, which is Clinton’s policy. You’re saying that that policy of containment isn’t working, so you’re contrasting your policies with Clinton’s policies, so no, I’m not going to change it.” He didn’t like the question at the end of the movie where I said, “Sir, why are you doing this? Why are you talking to me?” He felt that his farewell ceremony wasn’t long enough, that it should be truncated.

Did he like the film though, overall?

I don’t know. I know that there are things that he doesn’t like in it. But I really don’t know.

A big reason why McNamara opened up and admitted he was wrong was because there was enough distance between the present and Vietnam. So why did you go after Rumsfeld now? Why not wait, I don’t know, five more years?

Because the book came out. I read the book, became aware of the memos, and I thought there was a movie here. There’s no appropriate time, really, to do anything. You do what you can do, when you can do it.

How frustrated did you get interviewing Rumsfeld? He’s so slick. It’s like chipping away at metal with a wooden stick.

I don’t think that that’s an inaccurate description. Incredibly frustrating. And he would’ve probably done another 20 hours of interviews, and I felt that I had what I needed to make a movie.

But even if you did interview him for 20 more hours, he probably wouldn’t have revealed anything else.

Yeah. And then while we were talking, he would do things like I’d bring up the so-called torture memos, and he starts denying that they were torture memos, and makes this big speech about how they were approved by the attorney general, blah, blah, blah, and then he says, “Chalk that one up!” It seems kind of cavalier when you’re talking about something that is, to me, a really disgraceful episode in the history of my country and something that I find incredibly embarrassing.

There are several instances of that in the documentary, where you’re discussing very serious subjects and he unleashes that blood-curdling smirk.

“What did you learn from Vietnam?” “Some things work out, some things don’t.” “Are you controlled by history, or do you control history?” “Both ... Neither.”

This has to be the reason why Rumsfeld has been so Teflon-y in office—he’s a bullshit specialist, and all of his circular logic maxims and philosophy are just bullshit, and he’s presided under only shitty presidential administrations, and done a pretty shitty job at every single one of his posts.

He tells a story at this secretary-of-Defense conference around the time of the fall of the Soviet Union and says, “It’s because of steadfast commitment over an extended period of time,” and he’s basically talking about himself. Me, me, me. He’s talking about Nixon recording everything because he saw himself as a world-historical individual. He talks about Tariq Aziz as though he could have just as easily been talking about himself, or Saddam, or the soldier in Walter Reed hospital who is thought to be a dead man, but miraculously recovers. It could be him! It’s a strange, solipsistic world where you’ve piled words around yourself like sandbags to prevent reality from ever seeping in.

The topic of war seems to fascinate you. Why are we in a seemingly constant state of war?

Because I think people are crazy. I talk very briefly about Shakespeare, and with Shakespeare, the motivating force of history is insanity, greed, jealousy, hate, power. Rumsfeld said, “Well, maybe that was true then, but it’s different now.” Then he reads this memo to Condi Rice where he basically tells her to shut up, you’re not in the chain of command, nobody wants to hear from you, and if you continue to talk out, I’m going to the president and I’m going to have you muzzled.

It’s a very relevant documentary, given what’s going on in Syria right now.

That it is. When I got the Oscar for The Fog of War, we were on the verge of an invasion of Iraq, and McNamara wouldn’t come out against the war publicly, but privately, and oddly enough in Canada, he would. And Rumsfeld has just come out against intervention in Syria. It’s somewhat ironic!

What’s your stance on intervention in Syria?

War has, as Rumsfeld points out in The Unknown Known, unintended consequences. When you go to war, you don’t know what’s going to happen. You don’t know whether you’re going to increase or decrease suffering. I don’t understand what’s going on well enough. I don’t think most people do.

I think people do understand that they thought the president they were voting for, Obama, would be less inclined to go to war than he has.

Less inclined to do this kind of thing, and that there would be far less of an aggressive foreign policy. Look at the speech Rumsfeld makes in the movie at the very end about how the Obama administration criticized the policies of George W. Bush, but many of them are still in place. What a strange, Looney Tunes world we live in.