Peter Bergen is CNN's national security analyst, a vice president at New America and a professor at Arizona State University. He is the author of " United States of Jihad: Investigating America's Homegrown Terrorists ."

(CNN) President Obama's top counterterrorism adviser said that she believes the United States and its allies are winning the war against ISIS and that the incoming Trump team needs to guard against the possibility of terrorism during the early part of the administration.

Lisa Monaco oversees a team of some 50 senior directors and other officials at the White House who are focused on counterterrorism, cybersecurity and homeland security. Monaco and her team guide a wide range of American policies -- from the fight against ISIS, to how to guard against hackers on key infrastructure in the States, to how to mitigate the effect of emerging diseases.

Monaco previously ran the National Security Division at the US Department of Justice, which is in charge of prosecuting terrorism and espionage cases, and before then she was chief of staff at the FBI.

We sat down Thursday at the Defense One Summit in Washington to talk about the Trump transition and the fact that its "landing teams" have not been in touch as yet with her or her team; the possibility that Guantanamo Bay will go back into service for suspected terrorists, including, perhaps, for American citizens; and the possibility that coercive interrogations of terrorism suspects could be reinstituted.

Monaco gave her assessment of the war against ISIS -- the group is losing and badly in her view --- as well as how other jihadist groups are faring, including the continuing long-term threat posed by al Qaeda's affiliate in Syria and what she believes the next administration needs to worry about most, including the possibility of a terrorist attack early in the Trump presidency. We also discussed what the US intelligence community has determined to be Russian cyberattacks on elements of the American electoral system during the presidential campaign.

The discussion has been edited for both clarity and brevity:

Peter Bergen: The Trump transition: Have they been in touch with you?

Lisa Monaco: Not me personally. We are ready to carry out the President's directions. The President's been very clear with his team that we are going to conduct a professional, smooth, comprehensive transition.

Lisa Monaco is President Barack Obama's top counterterrorism adviser.

Bergen: Given the fact that President-elect Trump's campaign was very bound up with the issue of terrorism, is it surprising they haven't been in touch with you yet? After all you are the top counterterrorism official in the country.

Monaco: What's important to understand is there is a process put in place. It's now preserved in statute -- the transition statute. There's a White House Transition Coordinating Council, of which I am a member, and we have had a number of meetings to facilitate the transition. Now that we have the President-elect and his team there are a number of steps they have to take to be ready to receive classified information, not only from the National Security Council but also across the government. No (Trump) "landing teams" have gone into any of these agencies while those final steps are being taken.

Bergen: The landing teams -- they would need to have top secret clearances to be briefed?

Monaco: It will vary, depending on what type of information they're receiving, but certainly individuals who come into the National Security Council, the Defense Department, CIA, will have to have appropriate clearances in order to receive information.

Bergen: And you have no idea who your successor may be?

Monaco: I do not.

Bergen: When you meet with him or her for the first time, what are the most important pieces of advice, or warning, that you would give that person?

Monaco: What's going to be critical for my successor is to make sure you're focused on the very complex and wide-ranging array of threats that we face today. It's everything from terrorist threats, cyber threats, emerging infectious diseases. It's an extremely complex environment in which we're operating, and so I will be walking my successor through that landscape.

But, broadly speaking, I'll also try to impart, the types of things I think they should be focused on: building a good team, making sure you're asking questions, trusting your instincts, and then, personally, I would instruct him or her to live close by because you're going to spend a lot of time in your office. And I would also advise that person to stock up on Vitamin D because, as you know, I occupy a windowless office in the West Wing of the White House, and when I'm not there, I spend the rest of my time in a windowless Situation Room, so he or she will need to get comfortable with that.

From Guantanamo to Mosul

Bergen: The Obama administration has not sent prisoners to Guantanamo at all, right?

Monaco: That's correct.

Bergen: So, there's nothing preventing the new president from sending prisoners to Guantanamo, including American citizens, potentially, as was discussed in the campaign?

Monaco: The President-elect has spoken on the campaign trail about keeping Guantanamo open. That's obviously not President Obama's view, it's not this administration's view, and from a policy perspective, there's nothing to stop the next administration from keeping Guantanamo open.

Bergen: Right, and similarly with so-called enhanced interrogation techniques, sometimes referred to as torture, the new head of the CIA could bring back enhanced interrogation?

Monaco: As a policy matter, I suppose that's possible. President Obama issued an executive order -- one of the first executive orders he issued -- when he came into office banning torture and banning enhanced interrogation techniques and taking the CIA out of the detention business. That structure was broadly codified in a statute last year.

Bergen: But, presumably, you could find a lawyer in the White House to write a memo that said certain enhanced interrogation techniques didn't rise to the level of torture.

Monaco: That wouldn't be a lawyer in the White House as a matter of executive branch practice. It would be a lawyer in the Justice Department in the Office of Legal Counsel, which opines on the definitive view of the law for the executive branch.

Is ISIS winning?

Bergen: Some have claimed that ISIS is winning. What's your view?

Monaco: I disagree with that.

Bergen: Because?

Monaco: I disagree with that pretty profoundly, actually, because, what has distinguished ISIL (another acronym for ISIS) is that it has operated as a hybrid threat -- an insurgent army; a terror group, directing attacks like we saw in I disagree with that pretty profoundly, actually, because, what has distinguished ISIL (another acronym for ISIS) is that it has operated as a hybrid threat -- an insurgent army; a terror group, directing attacks like we saw in Paris and in Brussels ; and as a social phenomenon, using social media to spew venom.

On all three dimensions, ISIL is absolutely losing. They're being rolled back from territory that they used to occupy in Iraq and Syria, losing some 50% of the territory that they used to occupy. As a terrorist group, they're on the run. The Defense Department has taken down a number of very senior leaders. And, in the social media space and in the messaging space, we have retooled our approach, whether it's with our counter-messaging tools or by engaging with the private sector.

Companies like Twitter have really scaled up their actions to stop ISIL from exploiting and abusing their platforms. The numbers I've seen recently is over the last year, year and a half; some 360,000 terrorist accounts, have been disrupted and taken down. That's 1,000 accounts per day. And places like Google are putting in place very kind of new and innovative ideas to redirect those who are searching for ISIL content to other content. So I think we've got them on the run, for sure.

Bergen: Is the threat level here in the United States and also in Europe declining? And also, with the transition and the new presidency --- we saw 9/11 happened early in Bush's presidency and we saw the "underwear bomber" plot early in Obama's presidency -- are you concerned about something happening in the early days of the new administration?

Monaco: Well I'm always concerned about something happening, and that's pretty much what I get paid for. But I think it's a fair question. And it's one of the reasons we are so focused on a smooth and professional and comprehensive transition. Because, particularly in the national security, homeland security, counterterrorism space, there needs to be a clear transition of what we know and what we're doing and how we're going about taking the fight to terrorists. We always have to be concerned. They are relentlessly focused on attacking the United States. We're all vulnerable to (ISIS-inspired attacks), and that is something we are very concerned about because it's much harder to detect. How do you know when something goes wrong in somebody's head and will inspire them to act? That person doesn't have to travel to get training and then travel back to conduct an attack.

Bergen: Clearly ISIS is in the process of Clearly ISIS is in the process of losing (the Iraqi city of) Mosul ; it might be a few weeks away. What happens to the "foreign fighters" (who joined ISIS from around the world) who aren't captured or killed? What is the plan? Are some getting away? Is the Turkish border really sealed?

Monaco: We've made a lot of progress on sealing and moving up the defenses on the Turkish border. The Turks themselves have taken a number of steps there. So I think the inflow of foreign fighters has been greatly diminished.

Bergen: What are the numbers that you're seeing now?

Monaco: So, the foreign fighter numbers are down considerably over the last year, year and a half. The height, I think, over the course of the conflict, some 40,000 fighters. But we've seen over the last year a 50%, I believe, diminishment in the number of foreign fighters flowing into the theater.

Now your question is the concern of, well, who's flowing out? And certainly we're concerned about ISIL moving south; we're concerned about ISIL foreign fighters traveling back and trying to flee, to conduct attacks in Europe and then, ultimately, to here. I think we have a number of defenses. The first is the ocean that separates us, so I do think Europe is more vulnerable when it comes to foreign fighter plots, as we have tragically seen in Paris and Brussels

The second is the architecture that was put in place by both the Bush administration and this administration, to shore up our travel protections, our screening mechanisms, our information sharing both within our country -- amongst our law enforcement and homeland security and intelligence communities -- and with our international foreign partners. I will be talking to my successor about continuing to focus on the information-sharing relationship with our European partners, because that is critical.

Russia and the DNC hack

Bergen: Some have claimed that Some have claimed that Russia wasn't behind the hacks on the Democratic National Committee. What's your view?

Monaco: We've seen pretty clearly that the director of national intelligence and the secretary of homeland security spoke to this back in October, being quite clear that the intrusions and the compromises that we believe were directed by the We've seen pretty clearly that the director of national intelligence and the secretary of homeland security spoke to this back in October, being quite clear that the intrusions and the compromises that we believe were directed by the highest levels of the Russian government . Then we did substantial work to work with state and local governments and state and local administrators of the voting architecture and voting infrastructure in this country to shore up those systems as well.

Bergen: The electoral system in this country: Is it critical infrastructure like our power grid? Should it be treated as such in that an attack on it will have a proportionate response, similar to an attack on the power grid?

Monaco: I think it should be treated as such. And, in fact, we did so over the last six months as we ramped up for Election Day. Whether or not it is designated as critical infrastructure should not, I think, affect how we're treating it. The fact that it's not designated critical infrastructure does not impede what services and help that we can offer to state and local governments. And that's what we did with the run-up to the election.

Bergen: I want to throw out some names of terrorist groups. Just give us a brief assessment of where they are: al Qaeda Central, the group that attacked us on 9/11?

Monaco: Largely decimated. Spending more time thinking of their own security than how to plan and plot against us. But still determined.

Bergen: Al Qaeda in the Arabian Peninsula based in Yemen, which carried out the underwear bomb attempt?

Monaco: Al Qaeda's affiliate in Yemen, determined, persistent, particularly when it comes to external operations and aviation plotting against the United States.

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Bergen: Still?

Monaco: Still.

Bergen: They still have their key bomb-maker?

Monaco: (Bomb-maker Ibrahim al-Asiri) is still, as far as we know, in Yemen.

Bergen: Has he trained other people?

Monaco: We have to be concerned about that and that's the operating assumption, but I will say they have been under relentless pressure by our operations and in coordination with what we still believe to be the legitimate government in Yemen. I will also say the turmoil and devastation that's happening there because of the internal strife between the Houthis and the deposed government of Yemen has created a vacuum that AQAP has tried to exploit.

Bergen: What about Nusra (in Syria)? Are they playing a long game? ( What about Nusra (in Syria)? Are they playing a long game? ( Al Nusra Front renamed itself Jabhat Fateh Al-Sham this year, but the US government continues to view it as an al Qaeda affiliate.)

Monaco: I'm concerned they are trying to play a long game. Nusra is in essence al Qaeda in Syria and is now the largest al Qaeda affiliate.

Bergen: How many people?

Monaco: The estimates really range, but the people I'm most concerned about are the al Qaeda veterans who began a couple years ago to take up root in Syria in the ungoverned space left by (President Bashar al-Assad's) brutality on his own people to have a space to plot and plan against the United States, which is why you saw in September of 2014 that we initiated military actions to take out those leaders and to take out those plotters.

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This is another area where I will focus with my successor. I will argue the next team should be relentless about going after al Qaeda in Syria because we cannot let them take advantage of the chaos in Syria to mount a long game against us.

Bergen: Are you concerned about a son of ISIS or the grandson of ISIS? After all, ISIS is merely the son of al Qaeda in Iraq?

Monaco: I am because I am concerned about the underlying conditions that have allowed ISIL to take root. And really what that comes down to is grievances that are unaddressed and rising sectarianism across the Middle East, and until we address those issues and until those governments can get a hold of those issues I worry greatly that we and our partners have a continued challenge on our hands, which is why President Obama has taken the last eight years to put in place a sustainable, transparent counterterrorism architecture that can withstand a long game when it comes to fighting the terrorist fight.

Bergen: Final question: What will you be doing on January 21, 2017?

Monaco: Napping.