GEOFF BENNETT: U.S. officials say they are closely monitoring the situation in Syria, where 900 U.S. troops are still stationed mostly in the country's Northeast.

Jon Finer is the principal deputy national security adviser, and I spoke with him moments ago.

Jon Finer, welcome back to the "News Hour."

President Biden said yesterday that the sudden collapse of the Syrian government under Assad is a fundamental act of justice, but he said it's a moment of risk and uncertainty for the Middle East.

What are those risks, and what is the administration doing to mitigate them?

JON FINER, U.S.

Principal Deputy National Security Adviser: Well, Geoff, let's just not lose track of the opportunity side of this before we get to the risks.

And the opportunity here for the Syrian people is to have their first experience with a government free of oppression in many generations, after 13 years of just an excruciating, violent civil war.

That is the opportunity that presents itself by the fall of Assad.

The risk, of course, is that the groups that toppled Assad, some of them have their own checkered history, history with human rights abuses, with violent extremism, with terrorism.

Now, many of those groups are saying that they have changed, that they have reformed.

Many of them are saying the right things in the current moment, as the president pointed out yesterday.

But we will be judging those groups by their actions, by how they deal with this new moment of responsibility that's been brought about.

And I think the future of the Syrian people is going to depend on the choices that they make.

GEOFF BENNETT: The leader of Syria's rebel offensive, Abu Mohammad al-Jolani, he is said to have evolved from his past as a hard-line jihadi extremist.

What's the current U.S. assessment of him, and are the terrorist designations of him and his group still warranted?

JON FINER: Those designations very much remain in place because those designations are based on actions, not just on words.

And so the United States is going to be assessing in real time the choices that these groups make and that their leaders make.

Again, we have seen some of the comments made by Jolani and others, some of which we found to be constructive.

But it's going to take a lot more than constructive comments to bring about a better future for the Syrian people, a future that includes a government that is inclusive, that's represented by all of the major -- that represents all of the major communities that make up Syria's population.

And they have got a lot of work to get to that point.

The United States will be supportive of that process as it plays out on the side of the Syrian people.

GEOFF BENNETT: On Saturday, as rebels race toward Damascus, president-elect Donald Trump posted on social media: "This is not our fight.

Let it play out.

Do not get involved?"

What is the U.S. interest in Syria, in your view?

JON FINER: Well, the U.S. has a number of interests in Syria.

First of all, the United States fundamentally believes that the people of Syria deserve a better future than they have had to endure over the course of both the recent civil war and generations of tyrannical rule before that.

But fundamentally for the United States, there is still a terrorist threat in Syria.

There is an ISIS threat in Syria that the United States has deployed troops to address, including, by the way, taking strikes just yesterday to continue to suppress that threat, as we have successfully done now across successive U.S. administrations.

The United States has partners and allies inside Syria, Kurdish groups that we have worked with over a period of years.

The United States has partners and allies on the borders of Syria, Israel and Jordan and Iraq and other countries, whose interests we are going to try to work with them to uphold.

So the United States has a number of interests that converge in Syria, and we want to stay engaged.

But where we agree with what President Trump said is that does not mean the United States should be deploying militarily to engage in the conflict that ultimately led to the toppling of Assad.

GEOFF BENNETT: I want to note for our viewers that background noise, the construction happening there at the White House.

It is, of course, a very busy time at the White House.

A follow-up question, though.

Has the Biden national security team been able to convey those views and coordinate, for that matter, with the incoming Trump team, not just on Syria, but on a range of pressing matters from the Middle East?

JON FINER: So, on the national security side, we have been able to engage in conversations with the incoming Trump national security team.

I won't get into the details of those conversations, and I wouldn't say they go as far as coordination, but we are keeping them informed of these situations as they unfold.

GEOFF BENNETT: Assad and his family have been granted asylum in Moscow, as we understand it.

What does accountability for Assad, who was a brutal dictator, autocrat, what does accountability look like right now for him?

JON FINER: Well, we certainly believe that Assad should be held accountable for the crimes that he perpetrated against the Syrian people.

Certainly, there has been, as the president said, a measure of justice delivered already by the sheer fact of his removal from office summarily and the fact that he was forced to get on a plane and fly out of his own country, where he has spent his entire life as part of the ruling family.

So there is a measure of accountability in that.

We'd certainly be supportive of more.

I suspect the Russians will have a different view of what Assad's future should look like, so I'd direct your questions to them.

But we would be all for Assad being held accountable further for his crimes.

GEOFF BENNETT: Finally, this is a rare moment of hope for the family of journalist Austin Tice.

He's been held in Syria since 2012.

Does his family have reason to be optimistic?

I mean, is there an opening here potentially?

JON FINER: Well, I should say, I have known Austin Tice's family, his mom and dad, for now more than 10 years and had the occasion to meet with them recently, as I have a number of times in my current job and previously.

These are good people who have been put through just an extraordinarily terrible set of circumstances.

And, obviously, nobody has suffered more as a result of this than Austin himself, who's now been missing in Syria,held captive in Syria for 12 years.

It is our belief, our assessment that Austin is alive in Syria, and we are going to be doing everything we can to reunite him with his family.

Beyond that, we don't have further information to provide at this point.

But we are very much seeking information about his whereabouts, because he deserves to come home.

GEOFF BENNETT: Jon Finer, principal deputy national security adviser for the Biden administration, thanks again for your time this evening.

JON FINER: Thank you.