For a quarter century, Ted Koppel hosted “Nightline,” one of the most popular newscasts in the United States. Famous for his interviews, Koppel covered a broad range of domestic and international topics and won numerous Emmy Awards. Since leaving the show, in 2005, Koppel, who is eighty-three years old, has become a contributor to CBS’s “Sunday Morning.”

One of Koppel’s most frequent guests on “Nightline” was Henry Kissinger, who celebrated his hundredth birthday in May. That month, Koppel did a long interview with Kissinger, whom he has called a friend, for CBS. Although Koppel very briefly noted the controversies surrounding some of Kissinger’s policies when he served as national-security adviser and Secretary of State in the Nixon and Ford Administrations—which include, but are not limited to, bombing Vietnam and Cambodia, supporting genocidal policy in Bangladesh, and overthrowing a democratic government in Chile—the conversation mostly served as a celebration of Kissinger’s long career.

I recently spoke by phone with Koppel to discuss his friendship with Kissinger, and how he balances it with his role as a journalist. Our conversation, edited for length and clarity, is below.

When you were hosting “Nightline,” you had a reputation of being a tough interviewer. What did you try to accomplish in interviews, and how did you see your role?

Well, I saw my role as being—insofar as humanly possible—an impartial arbiter of information. Quite frankly, forty or fifty years ago, we didn’t think that much about whether someone was on the left or on the right. We have become much more conscious of that over the past twenty years.

I saw my role as being not only an arbiter but someone who would try to extract as much objective information as I could. It sounds a little bit romantic now, but I think many of us in those days grew up believing that was our job.

You feel li