It is not the celebration we're planning even just a few weeks ago, but it is a milestone worth noting.

It was 40 years ago.

This broadcast officially became Nightline and end of the day, accounting of source of a major crisis far from our shores.

Back then, Iran was ground zero.

Tonight, the threat is much closer.

Much of the world held hostage by a virus that kills indiscriminately.

My co worker, Juju Chang, was fortunate to talk with the man who anchored this program solo.

Back at his birth for decades, Ted Koppel informed and comforted this nation tonight.

Why he's worried about the most vulnerable today.

Hello, Ted.

I'm so pleased to see you looking so well and so glad you could join us tonight from your home office.

Oh, aren't you nice?

Thank you.

It's good to be with you.

Well, it's a bit of nostalgia, perhaps, but you helped launch Nightline during another critical moment in our nation's history, which was the prolonged Iran hostage crisis.

Nightline began, as you may recall, as something called America held Hostage Day 30 Day 100.

Well, there was a national obsession with that story very similar, in a sense, to what we find now, except that American lives were not as directly affected as they are now by the Corona virus.

This is a much bigger crisis, and I hope it doesn't last a cz long.

That one, as you may recall, lasted over a year 444 days.

You've also dedicated nearly two decades to another mission, which is fighting C o p d.

The ravages of chronic obstructive pulmonary disease, which your wife grace and has struggled with.

I don't think people understand how much of a national problem COPD is and how relevant it is to what's going on right now, because Corona virus, as most of your viewers probably no attacks the lungs and COPD is chronic obstructive pulmonary disease.

It kills 155,000 Americans a year, and people with COPD are probably more vulnerable to the Corona virus than almost any other group.

And so, during this time of crisis, hell of you and grace and been practicing social distancing and keeping yourself safe, Grayson has been training me in this art for a long time.

We have been doing elbow bumps rather than handshakes, washing our hands constantly.

And yet, when you look at the wider, vulnerable population, how do you calibrate that major message?

How do you get people to take it seriously for those who are vulnerable?

Unfortunately, I think we find that people only begin to take things like this seriously.

When someone in their circle becomes critically ill or even worse, tragically dies.

We're going to see a great deal of that in this country of in the next few weeks and months.

Wake up.

I mean, it's it really is too serious.

It's going to be too damaging.

Ted.

So much of your legacy here at Nightline was to be a calming voice in the midst of uncertainty and this type of national crisis.

What would you say to people who are having a hard time keeping perspective?

Um, I would say it is time, more than ever in this country to come to the realization that what we need more than anything else is reliable, credible journalism.

The fact that so much information is being conveyed by people who have no background in journalism whatsoever, but who do have the ability through the Internet to communicate absolute nonsense and sometimes damaging nonsense over the Internet.

This is a time when, rather than questioning the credibility of the media, we need to reinforce it.

It's what we tried to do 40 years ago in a time of crisis and what I know you're trying to do today.

Well, Ted, that's indeed your legacy.

That's Nightline's legacy.

I'm so glad you could join us tonight.

This is certainly a time when truth and science and fax matter, So thanks be well and take care of yourself in gray sand.

You on the other side.

Thank you.

Our thanks to Juju and Ted.

Hi, everyone.

George Stephanopoulos here.

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