Robert Mueller became FBI Director one week before the 9/11 attacks, serving until 2013. He tells IBA journalist, Ruth Green, how the intelligence landscape has changed and discusses the ongoing terrorism, cyber and data sharing challenges.

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Ruth Green (RG): Prior to joining the FBI, you were in the United States Marines for a period of time and worked as a prosecutor. How have these experiences helped you in terms of the foundation for joining the FBI?

Robert Mueller (RM): I was in the Marine Corps after college for three years and did a year in Vietnam. The Marine Corps teaches you some basic leadership principles: your troops always eat first; don’t ask anybody to do anything that you wouldn’t be willing to do yourself, along those lines. During the training, you’re put out with a squad of 10 or 12 persons and you’ve got to lead them on getting a particular objective. So that was tremendously useful.

And law school was helpful in giving [me] confidence in understanding the law and how the law thinks. Then I had a number of stints as a prosecutor in San Francisco, Boston and in Washington, DC. Those experiences included substantial periods of time on the Pan Am 103 Flight investigation. The joint investigation we did with the Scottish was one of the first of its kind.

Later, I did a tour with the US Attorney’s Office in Washington, where for a couple of years I prosecuted homicides only. That’s when the city was going through substantial turmoil as a result of the crack [cocaine] epidemic.

RG: You mention Pan Am 103, also known as the Lockerbie Bombing. At that time, it was one of the most severe international air terror attacks we’d seen. What was it like being involved in that type of investigation?

RM: On the one hand, it was tremendously interesting: we had very close relationships with prosecutors’ offices in Scotland, as well as our counterpart agencies. When you spend time with the victims’ families, it really sears you. It gives you an insight into terrorism: the devastating effects that terrorism causes to the families of the victims. That’s something you never forget.

RG: And that, presumably, was something you reflected upon a week after you were appointed as Director at the FBI, when suddenly you were faced with the terrible scenario of the 9/11 attacks?

RM:Yes, I think we’ve come a long way to emulating what we did in Pan Am 103 in terms of international cooperation, joint investigations and exchange of information – all of which we did quite well with the Lockerbie case. After September 11th, an international terrorism incident, we aspired to replicate what we put into place [then].

RG: 9/11 really changed the priorities of the FBI and its modus operandi. How would you describe that change?

RM: I had never fully understood our role to be preventing attacks. Yes, preventing the theft of secrets and the like, but I thought along the lines of handling Pan Am 103: ‘it’s happened and our investigation [involves finding] who was responsible and bringing them to justice’.

So I was somewhat taken aback when during my first briefing of the US President after September 11th, I start telling him about what we’re doing to bring these persons to justice and the President stops me and says: ‘Well, I want to know what the FBI is doing to prevent the next terrorist attack?’. I had not thought of that and felt hugely out of place. In the days, weeks, months afterwards, when I did brief the President, the question was always the same and my response was always: ‘This is what we’re doing to try to prevent the next terrorist attack’.

RG: The US Patriot Act was introduced following 9/11 and the 2001 anthrax attacks. How do you feel the Act helped the FBI?

RM:Prior to September 11th, there was a wall between the FBI and the CIA and the intelligence side, national security side and the criminal side. But the Patriot Act knocked down those walls and enabled us to become very close partners with the CIA. They operate under different rules than we do in terms of collecting information, because we’re inside the US and we generally collect against US citizens.

Consequently, the Act made a huge difference in terms of enhancing our capabilities to work together and ultimately to prevent terrorist attacks.

RG: Do you feel, looking back, that there was any downside to the Patriot Act? I’m thinking about the impact it’s had on the Muslim community with regards to profiling.

RM: People ascribe to the Patriot Act a number of the concerns they had which are not necessarily addressed by the Act. So, no, I have not seen any particular provisions in the Act that I thought were over the line. It was appropriate at the time.

RG: In what ways does the FBI try to work with Muslim communities that are helping to provide information?

RM: In the wake of September 11th, I very quickly sent out a memo to each of our field leaders in the 56 field offices, an admonition  to seek out, befriend and develop a relationship with Muslim communities in their territories. I would also meet periodically with the national leaders of the Muslim community and explain to them what we’re doing, how we’re doing it. And I would probably finish by saying ‘you can help us and you are maybe the most hurt if you do not... so we need your help.’ And most times, we would get it.

RG: Do you think anything has changed since your time as FBI Director in terms of the threat? Obviously, we’re dealing with the rise of ISIS and other non-state actors and groups.

RM: What has changed is that, with the internet, those persons who have no ties to a terrorism group, but do have a computer and access to the internet, can be radicalised; can be taught; can be encouraged to undertake actions by themselves. [Everyday] pressure cookers were used in the Boston Marathon bombings. It will become apparent that [the latest New York bombings in September 2016] used the same template, pretty much the same ingredients and the same mechanism – as the Boston Marathon bombers and they got that off the internet.

RG: The prevalence of the internet could make cyber security almost a bigger immediate threat?

RM: The cyber threat, depending on how and where and the like, can overtake and overshadow terrorism, although it’s not going to in the near future. We’re developing a response in the cyber arena based on what we learned in responding to 9/11. We’ve built up the expertise, especially with persons such as software designers and hardware manufacturers who became agents and they are better able to handle those types of investigations. We’ve brought on board 100 computer scientists in the last two or three years who back up the agents doing investigations.

We have, around the country, more than 56 cyber taskforces – so more than our divisions –where we have state and local law enforcement working closely with us and we have a very close relationship with the National Security Agency (NSA). They collect outside the US, we collect inside the US, but they’ve got expertise that we want to use on occasion. We have a number of people working with GCHQ in the United Kingdom and a number of agents embedded in other places in Europe and Asia.

RG: Technology is such a big challenge to the FBI and generally to intelligence and security agencies around the world. Why do you think certain tech companies – let’s take Apple as an example – seem to be going out of their way to try and protect their clients’ data, even when they know they could be providing some kind of information that would be helpful in a counter-terrorism investigation?

RM: There are a number of factors. One of them is they believe they are doing the right thing by focusing primarily on their customers’ privacy. Encryption is tremendously important individually. How you get around that; how you get the information that you need pursuant to a court order, is something that still has to be worked out.

I absolutely think [tech companies are] as patriotic as anybody else, but their emphasis is a bit different to our emphasis. That’s going to be worked out by Congress, hopefully, in the next session.

RG: Is it frustrating, given that we were talking of looking to, say, the Muslim communities, or indeed anybody, to give you information if they see something suspicious and then you have these companies refusing to give this data?

RM: It’s very frustrating and I don’t know what will make the pendulum swing. One hopes it’s not a substantial incident where you find all of a sudden if you had been able to decrypt that information at the time you might have been able to save lives. It will take something like that, I think, for Congress to really look closely at how it can be changed to accommodate both sides.

RG: Conversely, why do you think it’s so hard for foreign governments to get information from US-based internet service providers such as Google or Yahoo?

RM: Because there’s a fairly laborious, time-consuming, paper-driven process in place to make that happen. It’s one of the areas I absolutely believe they ought to look at and expand, modernise and digitise, to make that information more readily available to our counterparts overseas.

RG: There is currently a draft proposal in Congress, and I think it links to the UK, on working with allies generally in this regard.

RM: I understand they are talking about some accommodation with the UK and I don’t know whether they’d expand it beyond the UK, our closest partner. I’m not certain where that is, but my understanding is there are discussions about having some sort of mutual legal assistance treaty process that will expedite the ability of [UK] agencies to get the information they need.

RG: Another related area is bulk collection of data. Quite a lot of the big multinationals get upset with the state if they want to collect it, but then they do it themselves. Is this hypocritical?

RM: In some sense, people don’t distinguish between interception of the content and the metadata. Under US laws, the metadata is not protected by the Fourth Amendment. So to have a database that enables you to go after telephone numbers of would-be terrorists makes some sense [after meeting] a standard [by going] through [a] court.

One of the hijackers on September 11th was thought to be in Southeast Asia. The NSA had the ability to intercept phone numbers off a Yemen site, a safe house, so they could find out who called from Yemen. What they did not have the capability of doing is knowing what number from the US was calling this Yemen safe house. If we’d had that, we perhaps could have stopped the attacks, because the hijacker [turned out to be] in San Diego. If we’d had that, it would have been very easy to go to the [NSA] database constructed under Section 215 of the Patriot Act, run the Yemen number and see what numbers in the US were calling the Yemen number. So this took away from us one of the tools that the 9/11 Commission thought we should adapt and utilise. That’s an example of the use of bulk data.

RG: Do you have any views on how the UK’s vote to leave the European Union will affect the data-sharing abilities between the UK and the US in light of the fact that the UK won’t have that sort of access to information elsewhere in Europe, where we’re seeing a number of terrible terrorist attacks at the moment?

RM: That’s an interesting question. It may enhance the exchange because the American authorities might have been concerned [that] if we provided [data] to the British, because they [were] a member of the EU, that information will go to other members of the EU. Now, with Brexit, that isn’t a problem. So it may loosen up some of the bilateral exchanges between US and the British authorities, although it’s hard to determine whether that actually would [need to] happen -- we’ve always had such a good relationship with our British counterparts; I don’t think [Brexit] will make much difference to our relationship.

RG: Looking back, you served as FBI Director under two US Presidents and were the second-longest serving Director after Edgar Hoover. How much more effective are things now?

RM:In 2000, we had about 27,000 personnel total and at the end of the decade we had about 35,000. And our budget went from approximately $3bn to almost $9bn. So huge changes in terms of the resources given to us to try to address terrorism and cyber threats.

There was also an understanding that the Federal agencies had to work closely together. Beforehand, we had never got on particularly well with the CIA and vice versa. Part of it was statutory – the Patriot Act did away with that wall – but the other was that we had different cultures. Today, the FBI, NSA, Homeland Security, the CIA and others work very closely together. It’s completely different to how it was on September 11th.