Betsy, I hate to be a competitive journalist, but when I read the report about “The Sixth Extinction” in the U.N. report, I said, The New Yorker had that ten years ago, when you published it, in 2009, the very same thing. What is the difference between 2009 and 2019 in terms of the extinction of hundreds of thousands of species on the planet Earth?

Kolbert: Well, I think that it’s one of those cases where, as I’m sure Bill would say, you don’t like to see the news bearing out what you said. But, in this case, you know, the only difference is more documented destruction, really. And a lot more studies piled on the ones that were available to us five, ten years ago. But the general trend lines—an accelerating trend line, I do want to say, of human impacts—but the general trend line of biodiversity loss, which has been recognized for quite some time now, it’s all just playing out according to plan, unfortunately. And what this report does, I think, it’s really trying to, (a), raise the alarm, but, (b), really pointing to, there seems to be this strange disconnect, once again, out there. And it’s true that global G.D.P. is larger than ever. And at the same time species loss and destruction of the natural environment, natural world, other species is also greater than ever. And those two things are very intimately linked, and if you only pay attention to the G.D.P. part, you might say, “Oh, everything’s fine.” But I think what the point that this report is really trying to make is, those lines are going to cross. People are still dependent on the natural world—all the oxygen we breathe, all the food we eat, all the water—you know, these are biological and geochemical systems that we’re still dependent on, for better or worse, and we are mucking with them in the most profound ways. I think that that is the message, the take-home message of that report.

In other words, this so-called soaring economy that we’re enjoying now is the worst kind of illusion.

Kolbert: Well, once again, it depends on how you measure it. If you measure it by stuff that we’re producing, I don’t want to say it’s an illusion. But if you look at the other side of that, the cost it’s taken on the natural world, everything from land use gobbling up habitat to plastic pollution in the oceans. The list goes on and on and on. And the question of, can you sustain that over time, we haven’t been at this project very long without really wreaking havoc with the systems that sustain us. I mean, there are two issues here. And I think they have to be separated to a certain extent, intellectually if not biologically. And one is, could humans go on like this for quite a long time, just letting the rest of the world decay around us? Is that O.K.? You know, for us as a species to just do in a million or more other species, just because we are enjoying a better and better standard of living, is that O.K.? That’s one question, and then the other question is, can that happen? You know, just physically, are we capable of sustaining this, with all of these other trends going around, or are we really threatening our own life-support systems? And I think this report is suggesting very significantly that we are threatening our own life-support systems. But I think that the other question of the ethical stance that we take toward this is also extremely important.

And yet, for years and years, if you betrayed the fact that you cared about this, you were described as a tree-hugger and mocked.

Kolbert: Well, and that’s still true. I mean, we are arguing in this country right now. Even as I speak, and we speak, this goes back to the Trump Administration, and how they’re systematically trying to unravel a lot of very basic environmental protections in this country. We’re going to argue over the Endangered Species Act, which actually has been quite successful, in its own modest way. If you are a species, you get on the list, you have to have a recovery plan, and those species have tended to survive—not necessarily thrive, but survive. And now we’re going to argue about whether we should even be doing that. So these arguments are never-ending and, you know, pitting human welfare against the welfare of everything else, that doesn’t seem like a winning strategy over the long run.

Bill, I was really interested to read that you think that the great climate-change document of our time is by Pope Francis.

McKibben: Well, I think that the encyclical that he wrote three and a half years ago now, “Laudato Si,” it is amazing. Mostly because, though it takes off from climate change, it’s actually a fairly thorough and remarkable critique of modernity. And it talks really about precisely the things that Betsy has been talking about—understanding this as, yes, a problem of physics and of the need to put up a lot of solar panels and wind turbines, which we now can do because the engineers have made them affordable, but also understanding it as a problem of human beings and their relations with each other. As Francis points out, the last forty years, this period of time when we’ve worshipped markets and assumed they solved all problems has not only spiked the temperature through the roof, it’s spiked inequality through the roof. And the two are not unrelated.

How are they related? What is the essential relationship between the two?

McKibben: One of the things I spent some time doing in this new book is kind of teasing out the history that begins with Ayn Rand and kind of reaches a first zenith in the Reagan Administration, in 1980. The idea now in the air that we breathe, literally, that government is the problem, that if you leave corporations alone they’ll get done what needs doing, this reigning ideology came just at the wrong moment. It came at precisely the moment when we actually needed governments to be doing something very strong to deal with climate change. And that combination of ideology and interest has been enough to suppress our reactions in the crucial thirty years.

But have other governments that are less capitalist-oriented been any more successful in tamping down climate change than the United States?

McKibben: Sure. The first thing to be said is that same period was the period when the U.S. was ascendant over the rest of the world, so it held sway to some degree everywhere. But, go to Germany and look at what they did, beginning about 2000, with this law that made it easy for people to put up renewable energy. There will be days this month when Germany generates way more than half the power it uses from the sun, which is saying something, because no one ever went to Germany on a beach vacation, you know. Look at Northern Europe, at Scandinavia. I mean, they’re doing remarkable things. The engineers gave us an enormous gift. They dropped the price of renewable energy ninety per cent in the last decade. In China and India, thank God, that’s resulting now in very, very rapid expansion of renewable energy.

You wrote a wonderful piece for The New Yorker about solar panels in Africa. And yet you’re very—I think both of you are very wary of an excessive emphasis on technological transformation to solve all problems in climate change. Am I right?

McKibben: Well, technology is going to help enormously. We obviously have to produce a lot of electrons, and now we can, with renewable energy, but we can’t do that job—or the job of energy efficiency, or the job of starting to relocalize economies—we can’t do that without mustering political will. The reason that we build movements is not so much to pass particular pieces of legislation. It’s because one tries to change the Zeitgeist, the sense of what is natural and normal and obvious and coming next. And when you win that battle, then legislation follows. We’re getting closer. The polling last week showed that, for Democratic voters, anyway, climate change is now far and away the most important issue going into these primaries. That’s something that would have been unthinkable even a few years ago. And it’s a sign that all the movement-building, all the science, all the writing, all the engineering are reaching some kind of head, one hopes not too late.