… What was it like [at the Justice Department on 9/11]?

It was actually strange. It was eerily strange, because usually the Justice Department, like most federal agencies, is usually bustling with activity. But it was completely empty except for the command center, which is a highly secure, protected communication center in the Justice Department where all the people who were working on national security issues went, which was enormously busy there, and then at the FBI across the street. But aside from that, the city was empty to the point where I tried to find some food for dinner -- couldn't find anything to eat in the building except vending machines. There were no restaurants open. There was nowhere to get any food because the entire city had been evacuated.

So you think of a great world capital, busy and bustling, and on that day, actually eerily, it was completely silent and empty. It was really like one of those science fiction movies where someone wakes up and all the people are gone.

Talk to me a little bit about the emotions you felt.

So I think there wasn't really time on that day to really feel emotions, but one thing I remember at the end of the day was [my] drive home. I lived in Virginia, and I drove home over the 14th Street Bridge, which goes right by the Pentagon. And so I went home very late at night, probably 1:00 a.m. or 2:00 a.m. or something like that. And the most remarkable thing was all the lights were off, but the whole skyline was bright because of the flames in the Pentagon. It was like a big bonfire because they hadn't put the flames out yet. And I just remember that scene coming across 14th Street Bridge, which is usually -- that side is usually dark at that hour, and seeing huge flames coming out of the Pentagon, that certainly is [something] I don't think anyone ever expected to see in our lifetime.

What were you working on that day?

Well, the first thing we immediately started thinking about who was responsible, whether this meant the United States was at war. For the people who worked on the pure legal issues, that was the first primary question. Were we a nation at war? What did that mean legally and in terms of the powers of the government? What did that mean legally in terms of relationships with Congress, authorizations from Congress that would be necessary? Would what happen if the United States could immediately figure out where the perpetuators were? Would the United States use force against them?

So a lot of it [was] questions which you wouldn't be surprised that we were thinking about, which would eventually became relevant when the invasion of Afghanistan started. ...

A lot of people I talked to for the purpose of this film and other films say it really felt like something significant had changed, that something really was going to be different in America. Did it feel that way for you?

My academic career is about war powers and so on. There are two kinds of war that the United States fought. There are these kind of total wars where the country mobilizes like World War II, World War I and the Civil War, and everything does change at home as well as abroad. And I didn't think this was going to be a war like that actually, because we weren't facing any sort of threat to the existence of the country posed by another nation like Germany in World War II.

So I actually thought this war would be more like the wars during the Cold War period, where we had a lot of conflicts abroad that the United States was involved in, but throughout we had pretty normal peacetime affairs and legal relations. There was no mobilization of the economy during the Cold War.

And I think, after thinking about it for that first day and looking at all the authorities the federal government had and what Congress could do, I didn't think a lot of them would be necessary, and because once it was discovered or thought that this was really a terrorist plot with the Al Qaeda terrorist network, mobilization would not have been necessary.

But in terms of the emotions, I did have the feeling that we were entering uncharted territory, because before 9/11, terrorism had always been handled as a criminal justice problem, a law enforcement problem. And that's partisan; administrations of both parties treated it that way. So in response to a terrorist attack, our first instinct was to send the FBI out in a way and capture the terrorist and bring them back to the Untied States for a trial.

And one thing on 9/11 I think I immediately realized was that this was going to be a war, and criminal justice and law enforcement ways of thinking about terrorism were not necessarily going to work anymore.

What made you think it was a war? Because obviously there was certainly a presumption on the part of the FBI that they needed to be the ones interrogating people and building cases and getting information that we can bring into a courtroom.

I didn't mean to exclude the FBI or using the trials and prosecutors as a tool, but that wouldn't be the only tool, which it was before 9/11. And the reason for that was because of just the devastation of the attacks. Destroying the Pentagon and destroying the World Trade Centers are not things that criminals do -- that this was a kind of foreign attack for political purposes that we would associate with wartimes. Had this attack had been carried about before 9/11, during the Cold War, by the Soviet Union, in exactly the same way and hit exactly the same targets, would we have any doubt we were at war with the Soviet Union? So why should it matter that it was a terrorist group and not a nation-state that had attacked us on this way for us to decide whether we were at war?

Take me into the first serious meeting that occurred.

I can't say exactly what the subject was, but the meetings were done by phone, because the government was dispersed. The top leadership of the agencies were all sent to secure undisclosed locations, and so the meetings or conferences were initially done by video phone. I don't think it's any great secret that each of the national security agencies have the capability to link to each other at these locations by high speed communication networks, so they have these videoconferences with screens of everybody up on the wall and you're a person sitting there. And so there were those meetings on the first day.

Who were they with? Who was on the call?

The heads of the departments -- not talking about Veterans and Agriculture, but representatives from Justice and Defense and State and the White House and the NSC.

... Do you task yourself or does somebody say to you, "John, go give a good hard think about the constitutional issues that will face the president"?

We get requests for opinions from the attorney general's office and from the White House about these kinds of questions. It's not that we sort of spontaneously figure out what we're going to do. And also other parts of the Department of Justice are tasked with figuring out what eventually becomes the Patriot Act. ...

Are you aware almost right away that Afghanistan will be a theater?

No. I don't think so. People obviously had their educated guesses, but it took I think several days to pin down exactly how those hijackers were linked back to Al Qaeda in Afghanistan.

So once we know that it is Al Qaeda, once we know that it is probably Afghanistan and we're going to go in there, there will be people who up to battle in the field, there will be a tactical need for intelligence, there will be a strategic need for intelligence, what do you do?

Well, first let me say those issues about detaining people, interrogating people don't really come to the fore right away. I think the first big thing we start working on is getting authorization from Congress to conduct the war at all, whatever the war's going to be, even before it's Afghanistan. The White House and Justice Department negotiate with the members of the House and Senate about a statute to authorize a use of military force against anyone connected to the 9/11 attacks. [The] statute doesn't even mention Afghanistan, but it includes Afghanistan as a potential theater just because if you can show that Al Qaeda is based there, has relationships there, then it's sufficient to come within the statute. So that's really the first thing, the first way it comes up.

Is there any controversial element to that?

No. In fact, I don't think so. It's passed by large majorities of the House and Senate. And remember the Senate [at] this time is controlled by Democrats, and so we spent a lot of time negotiating with them about the exact language, but the finished product is a consensus document. The statute says use all necessary means to stop future terrorist attacks and to find those responsible for the past attacks. It's an extremely broad statute, but Congress knew what it was doing. I know that for a fact because we negotiated very closely with them about the wording.

Broader than any ever?

It is broader than previous authorizations because it's not limited to a specific theater, for one. So as you suggested, it doesn't even list Afghanistan. It could move. All right, if Al Qaeda went to Yemen, this statute will allow you also to intervene in Yemen to go after Al Qaeda. It also is not just Al Qaeda; it's anybody who helps or aids Al Qaeda, harbors them or protects them also falls within the authorization to use force. And it says use all necessary means to stop them, which includes certainly the use of force, but things short of the use of force, traditional powers you would have in wartime.

The statute says you can use necessary means to not just get at the people who carried out the 9/11 attacks, but anyone who protects them and supported them. So if a state like Afghanistan had protected and harbored Al Qaeda, which it did, they were [in] Congress's mind when it said you, the president, can use military force against another in response to the 9/11 attacks.

Was Iraq specifically mentioned ever?

No. I have to say this time we were not thinking about Iraq. Everyone during the congressional negotiations was thinking about Afghanistan.

Was writing this your responsibility?

My office and the White House counsel's office jointly worked on the statute. Even before I had gone to the Justice Department, I had read every previous authorization ever written by Congress in wartime, and every declaration of war. That's certainly my field, so I was sort of the natural person to accompany someone from the White House to negotiate these things to make sure the wording was right and that people were thinking about the right things.

You guys were over there working this thing out with Congress, and, as you say, it sails through.

Yeah, the people we negotiated with were [Senate Minority Leader Tom] Daschle's chief counsel and [House Minority Leader Dick] Gephardt's chief counsel and [Senate Majority Leader Trent] Lott's -- the representatives of each of the leaders of the House and Senate of both parties.

There's a lot of gravitas to this at that moment.

Yeah, people sort of realized the historical significance of what they were doing. People realized this was the first time the United States had been attacked since World War II, since Pearl Harbor, and the first time the American mainland had been attacked since the War of 1812, I guess it would have been. So I think people knew they wanted to do something to make sure that the president had the proper authority to really go after the people who conducted the 9/11 attacks. At the same time, they wanted to reassure the public that this was being done in a very deliberate way, that we weren't panicking, that there weren't going to be any kind of wild, unthoughtful responses; that we were going to be very deliberate and take our time figuring out what to do.

Were you leading the thinking, or was the White House leading the thinking and you were responding with answers? In other words, did the president want more than he got?

No, I think it was more that the White House said, "This is what we want to be able to do." And what they would just ask the Justice Department, say: "What is the law on this here? What do we need to have the law say in order to be able to reach that objective?" …

I can see from how that could be the basis for things to begin to flow: Does Geneva apply? Are they enemy combatants? Are they POWs? Are they wearing uniforms, and are they doing unlawful acts to women and children? The logic of it could flow from what you were talking about.

I think a lot of the logic flows from the two [questions] I had to answer right from the beginning: Is it war or not? And then, should they be treated the same as a nation or not? Because I think some people think, well, crime is just one sort of sphere with its own rules, and war is just one sphere and its own rules, and everybody in war gets treated the same. But that's not actually the case. War has different rules for a nation and different rules for people who choose to fight kind of like pirates who are outside the control of a nation.

And in the weeks after 9/11, then we start thinking about what happens when we catch other Al Qaeda members. Do we try them? Do we detain them? Where can we detain them? And those kinds of questions then start to come up or [we] start to think about them. But these are really driven by operational concerns. It wasn't, I think, hypothetical. It wasn't like people in the White House, the Justice Department, just sitting in a room and looking at the ceiling and saying, "Well, what happens if we capture Osama bin Laden?" As you start to prepare for a potential conflict in Afghanistan, you have to figure out what kind of facilities you even need.

So just to give one concrete example, the Geneva Conventions prohibit putting people in cells. The Geneva Conventions roughly look like the prisoner-of-war camp you saw in Hogan's Heroes or Stalag 17. Captured members of the enemy retain their military uniforms and their structure, and they live in barracks as a group, just like they were before they were captured; they just don't get to fight. If the Geneva Conventions applied, you would have to build barracks and let members of Al Qaeda live in groups. And so this is sort of an immediate thing the military needs to know, which is, what kind of facility do we need to build in order to place members of an enemy that we capture?

And it seemed obvious that they would want to put them in cells, becau