ANNOUNCER: This is the Washington Week Webcast Extra.

GWEN IFILL: Hello, I'm Gwen Ifill.

Joining me around the table: Tom Gjelten of NPR, Mark Mazzetti of The New York Times, Nancy Youssef of The Daily Beast, and Robert Costa of The Washington Post.

Let's start by taking a little - talking a little more about this increasingly bizarre 2016 campaign.

It appears to be operating, to me at least, on at least three levels: down in the gutter with tabloid accusations and online duels; in the states, where voters are still casting ballots and campaigns are jockeying for delegates; and on the sidelines, where political leaders like House Speaker Paul Ryan seem to be pleading with everyone to just settle down.

HOUSE SPEAKER PAUL RYAN (R-WI): (From video.)

Looking around at what's taking place in politics today, it is so easy to get disheartened.

How many of you find yourself just shaking your head at what you see from both sides of the aisle these days?

It did not use to be this bad, and it does not have to be this way.

Now, a little skepticism, that is really healthy.

But when people distrust politics, they come to distrust institutions.

GWEN IFILL: That felt a little bit like a cri de coeur.

But is anyone listening to Paul Ryan's plea?

ROBERT COSTA: Members on Capitol Hill are.

They're looking to him to try to be a standard bearer for civility and the kind of Republicanism they feel has been lost by Donald Trump's candidacy.

But what was striking listening to Speaker Ryan was the name he did not mention: Donald Trump.

And there is still a reservation in the upper ranks of the Republican Party to directly take on Trump and his entire candidacy.

They'll take him on when they think he's stepped out of bounds on certain specific issues, but they're really nervous about alienating those working-class voters who have been turning out in record numbers.

GWEN IFILL: I wonder if that's part of what we are seeing, this kind of unseemliness we're seeing roll out, in spite of Paul Ryan's concerns, about the two candidates fighting about each other's wives and hinting that they're going to take the other down on tabloid accusations.

It feels a little bit like Ted Cruz has figured the only - there are only two ways to take out Donald Trump.

One is to out-Trump Trump, and the other is to just survive.

ROBERT COSTA: I mean, watching it unfold on Friday afternoon was a just unreal experience as a reporter, maybe for just people out there watching the campaign, because they're talking about a National Enquirer story that has no evidence, other than speculation, it has no facts, yet it is dominating the 2016 campaign.

And you have the frontrunner calling his chief rival "Lyin' Ted," and he's saying the National Enquirer has in the past been a great source on stories like Senator Edwards.

I mean, it's surreal.

GWEN IFILL: "Lyin' Ted," with the apostrophe, in his statements.

ROBERT COSTA: Always with the apostrophe.

GWEN IFILL: Always with the apostrophe, and capitalized.

TOM GJELTEN: And in return he gets called a "sniveling coward."

ROBERT COSTA: "Sniveling coward."

GWEN IFILL: A "sniveling coward."

So that's - we've taken it right up there.

So, while all of this is going on on the Republican side, it casts a real shadow on the Democratic - likely Democratic nominee, as we keep calling her, Hillary Clinton.

But she's never managed to shake this email controversy, and it's boiled down into things which maybe are too technical for people to decide they're going to vote against her based on.

But one of the technicalities is what is secret and what is not, Mark.

MARK MAZZETTI: Right, and whoever she runs against - presumably, if she's running in November - this will continue to be an issue because it's lingering.

There are - there is an ongoing investigation by the FBI.

She has said publicly she's not going to be indicted.

I think that's probably a safe bet.

It doesn't mean that some of her staff might not get into trouble, either in some kind of a criminal charge or an administrative charge.

It's going to linger.

And the question on what is classified and what is not has been a question for a long time.

GWEN IFILL: That's her chief defense, right, that - MARK MAZZETTI: Right, her chief defense is that there's over-classification.

At the same time, you do talk to a lot of people in government who say that there's a double standard for the people at the top, who can trade in classified information and be loose with classified information, and lower-level people, who get prosecuted.

And there's a lot of evidence in the Obama administration of people getting prosecuted for this type of thing.

So this is something that doesn't quite go - will not quite go away.

GWEN IFILL: It's interesting, because in the primaries it hasn't been - in part because Bernie Sanders said I'm not going to do anything about the "damn emails," as he put it.

But it could still come back to haunt her, I suppose.

MARK MAZZETTI: Certainly.

It certainly should.

GWEN IFILL: OK. Well, let's talk a little bit about - let's go abroad for a moment.

Nancy, you wrote this week about something which also often gets overlooked in this time of terrorism and wars other places, but in this case it's Iraq - the old war, which we're supposed to be out of.

But increasingly, our footprint seems to be expanding.

NANCY YOUSSEF: Yeah, this week there was a very interesting development that came about under the worst of circumstances.

The U.S. lost a Marine, Staff Sergeant Cardin, and it was through his death that we learned that 200 Marines had been stationed in Iraq.

Now, originally we were told that they were there in a defensive position to provide security for advisers.

And then a few days later we see the Iraqis trying to move forward and move towards Mosul, and you had the Marines conducting operations with them, firing with them.

And so it was sort of a mission creep, and now you have the U.S. military ground forces involved in Iraq in a war that was supposed to be over, and we don't learn about it until something tragic happens.

You know, it's one thing when the military doesn't tell us about Special Forces going in, but this is a conventional force that went in and is going in to be on the ground with the Iraqis in the - GWEN IFILL: Who had dispersed into the hills.

NANCY YOUSSEF: That's right.

And try to take back Mosul, which will be the biggest and most difficult fight of the war.

It's their capital in Iraq.

It's the city they've held the longest.

And so it was really startling to see how those Marines were stationed there, what they were stationed for, and the challenge that they face.

They're there to back up Iraqis who were hiding in the mountains when they arrived because of the ISIS strikes that had come upon them when they arrived at the base a month before the Marines did.

GWEN IFILL: But so, slowly but surely, we are taking the lead once again.

Tom, we're going to go in the way back machine to another war everybody forgot about, where we actually saw a conviction this week.

And you covered it.

TOM GJELTEN: I did.

It was a real blast from the past for me.

I mean, Radovan Karadzic is no longer a household name, I can - I think we can say.

But he certainly was 20 years ago, the leader of the Bosnian Serbs - the political leader of the Bosnian Serbs, had command responsibility for decisions that ended up with the deaths of thousands and thousands of Bosnian Muslims.

He was arrested in 2008.

That's eight years ago.

This is a - GWEN IFILL: Long trial.

TOM GJELTEN: - justice system that works very slowly.

But you're right, he did get convicted on 10 out of 11 counts, including one count of genocide, and then nine counts of crimes of war and crimes against humanity.

So justice moves slowly, but it came to a conclusion this week.

GWEN IFILL: What happens, then, to him after a conviction like this?

TOM GJELTEN: Well, he was sentenced to 40 years with credit for time served, which is eight years.

So he's still got 32 years on his sentence.

GWEN IFILL: This is the international court, we should say.

TOM GJELTEN: So this is the International War Crimes Tribunal for the Former Yugoslavia.

So he's got 32 years left on his sentence.

He says he's going to appeal.

But, you know, this is not a judicial system that's got much of an appeal structure to it.

So I think we can assume - he's 70 years old.

I think we can assume he's going to be in prison for the rest of his life.

GWEN IFILL: The arc is long but bends towards justice, I imagine.

TOM GJELTEN: Seems to.

GWEN IFILL: Nothing like a Martin Luther King quote just before Easter.

Thanks, everybody, for joining us.

While you're online, you might want to check out my blog this week, where I ask you to weigh in on what feels to me like a new culture of meanness.

And we'll see you next time on the Washington Week Webcast Extra.