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Home » Transcript of Professor Jeffrey Sachs In Conversation With Richard Overy, Why War?

Transcript of Professor Jeffrey Sachs In Conversation With Richard Overy, Why War?

Read the full transcript of a conversation between Professor Jeffrey Sachs and historian Professor Richard Overy on one of humanity’s most unsettling questions: Why do we wage war? On Book Club with Jeffrey Sachs, premiered on Mar 4, 2025.

Listen to the audio version here:

TRANSCRIPT:

Introduction

PROFESSOR JEFFREY SACHS: Welcome to Book Club with Jeffrey Sachs. I’m really excited today to be speaking with one of the world’s great historians, a great historian, especially of World War II, but a historian of war in general. We’re speaking with Professor Richard Overy, the Honorary Professor at University of Exeter. He’s also was longtime professor of history at King’s College London. He is a graduate of University of Cambridge and a great scholar.

Professor Overy, thank you so much for the chance to speak with you about your new book. I’m going to hold it up as a paper because I read it as a Kindle. But this is the cover, “Why War?” And it’s a wonderful overview and discussion of the many perspectives of why war, ranging from the biology and anthropology of our species, to the motivations of war of those who take their nations into war, whether it’s the pursuit of power or the pursuit, they think, of national security or the search for resources and so forth. So it’s a great overview of this enormously complex, challenging, and central issue for humanity.

And it seems we’ve been surrounded by war non-stop. I feel as an American, my whole life has been lived with America at war of one kind or another, proxy wars, direct wars, covert wars, overt wars. So I immediately grabbed your book as soon as it appeared to better understand this. So thank you for being with me, Professor Overy.

PROFESSOR RICHARD OVERY: My pleasure.

The Structure of “Why War?”

PROFESSOR JEFFREY SACHS: We could start off. The book’s divided into two parts. The first part is a kind of fundamental view, why do we fight? And as I mentioned, that touches on biology, human psychology, anthropology, and ecology.

The second part is more from the perspective of statecraft, I would say. What are the motivations, as perceived by state leaders who take their nations to war, the pursuit of resources, beliefs, seeking power, seeking national security. Why did you structure the book this way? And how do you feel that these two different dimensions help us to understand your big question, why do we have so many wars?

PROFESSOR RICHARD OVERY: Well, the first part of the book is really aimed at the last, say, thousand years of human history. It’s really to look at where the origin of our belligerence comes from, and we’re a very belligerent species. Now, many historians date it really from the onset of the state, but I’m not happy with that. And there’s plenty of archaeological and anthropological evidence to suggest that small groups, whether it’s a Madi tribe or whether it’s a separate tribe from long ago, were certainly capable of what we should regard as warlike violence. It’s not war in the modern sense, but warlike violence, often exterminatory violence where one village finally decides that the next village is engaged in sorcery and they set out to punish it. So the first half of the book is really the longer perspective, you know, where does our urge to belligerence come from?

Why do we have almost every society worldwide by, say, four or five thousand years ago organized for war in some form or other? The roots, it seems to me, go a long way back. But the second part of the book is really about motives. Because if we think about the broader framework within which human beings have conducted warfare, we have to also look at it in terms of motives. And because human beings are conscious animals, you know, they have to find some way to justify what is they’re doing.

Seizing resources, defending belief, seeking power or security is not just a modern thing. It’s not just what states do. It’s also something that we can see tribal communities doing. And I think we can imagine that in all four cases, these are factors which also go deep back into the human past.

The Us Versus Them Mentality

PROFESSOR JEFFREY SACHS: This basic notion that I think runs through your first half, whether it’s the biology, the psychology, the anthropology or the ecology, the four headings, is all about the us versus them mentality in some sense. This extraordinarily sophisticated in some way, often suicidal, but sophisticated way that human beings draw boundaries between the inside group and the outer group. Is that correct in your view? I mean, that’s at the core of this?

PROFESSOR RICHARD OVERY: I think it’s very important. And I think you can take it back a very long way. The kin group, whether they’re nomads or it’s a tribe, the kin group is what matters and you defend the kin group against all comers when necessary. And that will usually or has usually involved some level of warlike violence. And dividing the world around you into them and us is something we still do today.

I mean, we can find plenty of examples in the twentieth century where people who actually live side by side as neighbors—take Bosnia in the Yugoslavia civil war. People who live side by side as neighbors can suddenly turn into the bitterest enemies, committing atrocities against each other. It seems extraordinary, but the human capacity to divide people into them and us, into the other and us, seems to me to have a long history. And psychologically, I think it’s very important explaining how human beings are capable of being belligerent against their own species.

PROFESSOR JEFFREY SACHS: I can tell you just a personal anecdote. I was asked by the last federal government of Yugoslavia, Prime Minister Ante Markovic, in 1989 to help advise on what was an economic calamity that had hit Yugoslavia, and it turned into a hyperinflation.