Mark Lynas on Nuclear War

Summary

Podcast Summary: The Good Fight with Yascha Mounk Guest: Mark Lynas
Episode: Mark Lynas on Nuclear War
Date: June 7, 2025

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Overview

This episode of The Good Fight delves into the under-discussed but existential risk of nuclear war. Host Yascha Mounk is joined by activist and writer Mark Lynas, author of Six Minutes to Nuclear War (and How to Avoid It), to examine the consequences of full-scale nuclear conflict, the realities and underestimated dangers of nuclear winter, the mechanisms that have (so far) prevented nuclear catastrophe, and what steps are necessary to reduce and eventually eliminate this civilizational risk. The conversation covers not only the grim details of nuclear warfare and its aftermath but also draws parallels to climate change activism as a model for building political movement against nuclear arms.

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Key Discussion Points and Insights

1. The Risk of Nuclear War: Existential and Neglected

• Modern Attitudes Toward Nuclear Risk

  • Nuclear war, while headline news during events like the Cuban Missile Crisis, has faded from urgent concern since the end of the Cold War, replaced more recently by anxiety about climate change, AI, and pandemics ([03:58], [04:32], [07:00]).
  • "Thinking or worrying about nuclear war feels a bit retro... it seemed to have disappeared completely." – Mark Lynas [04:32]
  • Compared to other existential risks, nuclear conflict is unique due to the immediate, near-total destruction it can cause ([04:32]).

• Existential Comparison with Climate Change

  • Climate change manifests gradually, with "off ramps" for adaptation or technological solutions; nuclear war has instant, catastrophic impacts ([04:53], [07:00], [09:02]).
  • "Nuclear war can destroy the biosphere in pretty much half an hour." – Mark Lynas [04:53]

2. The Mechanics and Consequences of Nuclear War

• Direct Effects

  • An all-out exchange (e.g., US vs. Russia or China, ~3000 warheads) could directly kill 300 million to 750 million—most people would survive the initial blasts ([12:48]).

• Nuclear Winter Explained

  • The true "kill mechanism" is nuclear winter: vast fires inject soot into the stratosphere, blocking sunlight and drastically lowering global temperatures ([10:38]).
  • "It gets heated up by the sun and gets higher and higher into the stratosphere... essentially becomes a veil which wraps around the earth and prevents sunlight reaching the surface." – Mark Lynas [10:38]
  • Worst-case (Nature Food 2022): Total darkness, freezing world temperatures, multi-year famine, global crop collapse ([10:38], [12:48]).

• Second-Order Effects: Famine, Societal Collapse, Cannibalism

  • Post-blast, nuclear famine is modeled to kill close to 7 billion, or 99% of populations in highly-affected countries ([12:48], [14:09]).
  • Mark Lynas details lifeboat ethics, food storage fantasies, and the logistical impossibility of preparing for such an event ([14:09], [15:05], [16:59]).
  • Societal collapse would manifest as violence, breakdowns of authority, and, with striking bluntness, cannibalism as a likely food source ([16:08], [20:06]).
  • "I talk about cannibalism because that's a fairly common occurrence in famines... it's quite likely that humans would eat each other and that's the main source of remaining food in years like 2 to 3 to 4." – Mark Lynas [00:01], [20:06]

• Long-Term Prospects: Not Total Extinction, but Devastation

  • Some populations, particularly in large food-exporting countries with small populations like Argentina and Australia, may survive in pockets ([20:06]).
  • However, survivors would exist in a shattered, non-technological world with limited resources.
  • "I think it's the kind of post apocalyptic society is very difficult to visualize. We don't really have many historical analogs." – Mark Lynas [00:01], [20:06]
  • The ethical dilemma of whether one would want to survive in such a world is discussed with reference to The Road and even Holocaust survival ([23:26]).

3. Nuclear History and Near Misses

• Development and Escalation

  • Overview of nuclear weapons development, the Manhattan Project, Hiroshima/Nagasaki, and the early US/Soviet arms race ([25:45]).
  • "The history of nuclear weapons...is that the Soviets got them very quickly...by the 50s you have an arms race..." – Mark Lynas [25:45]

• Cuban Missile Crisis: How Close We Came

  • On Black Saturday, a single Soviet officer's decision arguably prevented nuclear war ([26:49]-[28:58]).
  • "It was that close and that was after Kennedy and Khrushchev...seconds, seconds, seconds." – Mark Lynas [28:58]

• Other Incidents and Inadvertent Risk

  • Multiple false alarms, near-launches, and accidents have almost led to disaster.
  • Probability of inadvertent nuclear war is estimated at ~1% per year—statistically, a 2/3 chance over a century ([30:50]).

4. Proliferation and the Increasing Risk

• Effect of Nuclear Spread

  • As more countries (India, Pakistan, Israel, North Korea, Iran) acquire nuclear weapons, the chance of accidental or deliberate nuclear exchange goes up ([29:52], [30:50]).
  • "Every single year we're probably not going to have a nuclear war. But over time the risk in that sense accumulates to a very dangerous level indeed." – Mark Lynas [31:48]

• Regional vs. Global Nuclear Conflict

  • Regional nuclear war (e.g., India-Pakistan) would devastate those areas but have milder global impacts (several years of global cooling, global food reduction), whereas large-scale exchange would be globally unsurvivable ([34:26]).

5. Prospects for Containment and Prevention

• Is Limited Nuclear War Possible?

  • Doctrines like "launch on warning" and war games suggest that once nuclear weapons are used, escalation to full exchange is highly probable ([32:37], [33:57]).
  • "Six minutes to decide whether to respond to incoming missiles... obviously an impossibly short window..." – Mark Lynas [32:37]

• Lack of Preparedness and Political Discourse

  • Societies have not prepared for nuclear winter, don't store food, and lack the institutions to manage mass catastrophe ([15:05], [16:59]).
  • Nuclear risk has no equivalent grassroots movement to climate activism—a political void that needs filling ([35:54]).
  • "We have to start talking about it... there's a legal mechanism... for the full abolition of nuclear weapons... but I think it's important because there is a legal mechanism... for the full abolition of nuclear weapons." – Mark Lynas [35:54]

• Arms Control and Political Realities

  • Recent years have seen the erosion of Cold War-era arms reduction treaties ([35:54]).
  • Complete disarmament (global zero) requires verifiable, multilateral action—unilateralism is a nonstarter ([39:49]).

• Paradox of Deterrence

  • Existence of nukes arguably both deters total war and enables certain aggressions (e.g., Russia in Ukraine, North Korean regime survival) ([39:49]).
  • "We have to have a situation where humans can carry on fighting wars, but without the biosphere being destroyed." – Mark Lynas [39:49]

6. What Can Be Done?

• Building Political Will

  • The path to nuclear abolition is analogous to the climate movement: shift public consciousness, generate political pressure, and develop legal/international mechanisms ([45:35]).
  • "We have to have a significant political demand, at least in democratic countries, for a de escalation of nuclear risk. And that's not there at the moment." – Mark Lynas [45:35]
  • The Treaty on the Prohibition of Nuclear Weapons (TPNW) is little known but could serve as the legal anchor for future pressure on nuclear countries ([35:54]).

• Technological and Political Synergies

  • Changes in technology (renewables, nuclear power for peaceful means), economics, and politics interact; but “the politics comes first” ([45:35]).

• Hope vs. Cynicism

  • Despite a less optimistic geopolitical environment, activism and public pressure have changed what once seemed intractable (e.g., climate energy transition) ([45:35]).
  • "I've tried to do my part to raise attention to it... I just hope now that sufficient people realize that it's so—the risk is still there." – Mark Lynas [45:35]

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Notable Quotes & Memorable Moments

• On the End of Civilization:

  • "Nuclear war can destroy the biosphere in pretty much half an hour." – Mark Lynas [04:53]
  • "It's quite likely that humans would eat each other and that's the main source of remaining food in years like 2 to 3 to 4." – Mark Lynas [00:01], [20:06]
  • "It's inconceivable to store the amount of food that would be required to sustain the current global population." – Mark Lynas [16:59]
  • "I can't believe I'm talking about how to survive a nuclear war. The whole point is not to have one." – Mark Lynas [18:05]
  • "Is that a world I want to try and survive within? I'm not really sure it is. No." – Mark Lynas on post-apocalyptic survival [23:26]

• On Near Misses:

  • "It was that close and that was after Kennedy and Khrushchev... seconds, seconds, seconds." – Mark Lynas on Cuban Missile Crisis [28:58]

• On Activism and Hope:

  • "We have to start talking about it... for the full abolition of nuclear weapons." – Mark Lynas [35:54]
  • "The politics comes first. We have to have a significant political demand, at least in democratic countries, for a de escalation of nuclear risk." – Mark Lynas [45:35]

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Timestamps for Major Segments

• Existential Risks: Nuclear vs. Climate: [03:58]–[09:02]
• Nuclear War Scenario & Nuclear Winter Explained: [09:02]–[14:09]
• Food, Survival, and Societal Breakdown: [14:09]–[21:56]
• Personal Ethics of Survival: [21:56]–[23:26]
• History of Nuclear Arms & Cuban Missile Crisis: [25:45]–[28:58]
• Probability and Proliferation: [29:52]–[31:48]
• War Escalation & Doctrines: [32:37]–[34:26]
• Regional vs. Global Impact: [34:26]–[35:33]
• Political Pathways to Risk Reduction: [35:54]–[42:12]
• Challenges of Global Disarmament: [42:12]–[45:35]
• Lessons from Climate Activism & Hope: [45:35]–[47:34]

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Tone and Language

• Frank, occasionally grim, but committed to intellectual honesty and public service.
• Moments of dry humor and personal reflection, especially when grappling with the ethical and emotional stakes.
• Urges listeners to move from complacency to activism, paralleling the nuclear challenge with the successes and difficulties of the climate movement.

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Summary Conclusion

The episode forcefully argues that nuclear war, though often dismissed or relegated to the “worried but ignored” category of existential risks, remains perhaps the greatest immediate threat to humanity and civilization. While the technical means for devastation exist and have nearly been triggered by accident or miscalculation more than once, a political movement to abolish—or at least drastically reduce—nuclear arsenals is lacking. Drawing inspiration from the climate movement, Mark Lynas and Yascha Mounk urge renewed public pressure and political prioritization to avert the grim scenarios outlined and preserve the future of humanity.

Transcript

[Mark Lynas]

So it's not as if in this scenario everybody dies. But I think the kind of post apocalyptic society is very difficult to visualize. We don't really have many historical analogs, even from famines. I mean, I talk about cannibalism because that's a fairly common occurrence in famines and even in shipwrecks and plane crashes and things. So it's quite likely that humans would eat each other and that's the main source of remaining food in years like 2 to 3 to 4. But what happens in the kind of rebuilding scenario? I really have no clue. And now the good fight with Jasia Monk.

[Joshua]

There are some topics that are obviously incredibly important and yet they tend to fall into the background of our political consciousness. Perhaps top of that list is the risk of nuclear war, something that was headlines during the Cuban Missile Crisis and various moments of geopolitical tension, but that usually we sort of file away in our mental cabinets as something we should be worried about but are not thinking about too much. I wanted to make sure that we give that topic the attention it deserves in one of the conversations on this podcast. And so I invited my good friend Mark Lynas to talk about it. Mark is a really interesting writer and activist who got started thinking about the risks of climate change and as an environmental campaigner, but has now written a book called Six Minutes to Nuclear War

[Interviewer]

and How to Avoid It.

[Joshua]

In the conversation, we talk about what the world would look like after a major nuclear confrontation.

[Interviewer]

How many people would die in an

[Joshua]

initial war between, let's say the United States and China or the United States and Russia, and how many people would die in the ensuing nuclear winter, which,

[Interviewer]

spoiler alert, turns out to be much

[Joshua]

more deadly and even more gruesome than the original confrontation. We talk a little bit about why it is that so far we have not experienced a giant nuclear war. Whether we can learn from the things

[Interviewer]

that have avoided catastrophe so far and

[Joshua]

why, according to Mark, the risk of nuclear war just keeps adding up and keeps increasing. And finally, we talk about what political steps all of us can take to try and contain this risk. In the final part of the conversation, we also circle back to talk about the subject that Mark has written about for much of his life, which is climate change. One of Mark's best selling books was Six Degrees Imagining what the Planet will Look like under different scenarios, including the most concerning one in which it is 6 degrees warmer on average than it is today. Well, Mach now believes for that worst case scenario, it's sort of off the table. We're not going to get to 6 degrees. At worst, we're going to get to 2 or 3 degrees. So after a pretty downbeat conversation, we have a cautiously optimistic conversation about why it is that humans are to some extent succeeding in the fight against climate change, even as it remains a serious problem. To listen to that part of the conversation, please support this podcast, support the work we do here, become a paying subscriber, get ad free access to all full episodes of these conversations. And I'm throwing in a special discount today, so go to yashamonk.substack.com thegoodfight for 25% off your first year of subscription. That's yashamunk.substack.com A good fight costing you just about a dollar a week for the first.

[Interviewer]

Mark Lynes, welcome to the podcast.

[Mark Lynas]

Thanks, Joshua. It's great to be back.

[Interviewer]

You always have cheerful topics in store for us, from From Climate Change to Nuclear War Nuclear war is one of those things that we all learn to worry about at some point in our childhood. It's obvious that it's this kind of strange, looming danger hanging over humanity, and at the same time, it's usually in the background of discussions. Not since the Cuban Missile Crisis has it really been at the absolute forefront of the news. Where would you rank the risk from nuclear war relative to the other big existential risks facing humanity?

[Mark Lynas]

Wow. I mean, there's a lot in that. And I agree that thinking or worrying about nuclear war feels a bit retro. You know, it's sort of like since the end of the Cold War, we certainly my generation, I mean, I'm not sure how close in age we are. I think I might be a bit older than you, but I grew up with nuclear war being this thing.

[Interviewer]

But you have more hair marks, so it's okay.

[Mark Lynas]

I didn't want to judge, but we were all ready to die at pretty much any time before the Berlin Wall came down and suddenly the Cold War was over. And suddenly the risk of nuclear Armageddon seemed to have disappeared completely. We were friends with Russia and people stopped worrying about it. And I think people were very glad to be able to drop it from the list of existential risks that they had to spend any amount of time worrying about. And then, of course, climate came, and I've contributed to the sense of existential crisis that is attached to climate change with some of the writing that I've done. My book Six Degrees talked about climates, certainly in the extreme warming scenarios, as very much a catastrophic risk, not just to humanity, but to the planetary biosphere. And so that then became the preeminent, preeminent concern of this generation and certainly of younger people. You had Greta Thunberg and you had the pride of future movement, and. And that generation then grew up with climate being their existential risk. And of course, there's other ones and there's books about which existential risks are greater than which other existential risks, whether it's AI or pandemics or asteroid collisions or whatever. And we can get into ranking them, if you like. I actually had a piece in the Wall Street Journal recently co authored with Ted Nordhaus from the Breakthrough Institute, actually making the point as gently as we could that climate is an existential risk of a different nature in that there are off ramps. You know, the impacts of climate change manifest over decades or even centuries, if you're talking about the melting of the large ice sheets and multimeter sea level rise and so on. Whereas, of course, as we all know, nuclear war can destroy the biosphere in pretty much half an hour. I mean, doesn't take very long to get ICBMs in the air and striking and burning the major cities of the Northern hemisphere, which is the existential risk that it's not actually the bombs. It's not just the blast and the burning.

[Interviewer]

One of the things that's interesting here, and it's a gruesome thing to talk about, but I think it's actually important to be intellectually rigorous about it, is that the distribution of outcomes seems to me, at least intuitively, to be somewhat different. So climate change is a very serious risk to humanity. I think the likelihood that it leads to a significant number of deaths to a significant number of people's lives being impaired is perilously high. And all of those are very good reasons to worry about it, to make the fight against it a priority. It is harder for me to see a scenario in which climate change actually destroys humanity or even destroys, broadly speaking, our level of technological civilization. It's easy to imagine hundreds of millions of people dying, and that, obviously is a very, very bad thing. It's harder to see how climate change leads to either the death of 99% of humanity or sort of us being unable to sustain the level of technological advancement that we have as a species, whereas the risk of nuclear war is perhaps lower in the sense that a bad outcome is less likely. You might disagree about that, but I think it's easier to imagine, well, we somehow get through the 21st century without a nuclear war, and there's just no immediate downside. From having those weapons. But if the negative case is activated, it's much easier to imagine a scenario in which the vast majority of humanity dies, in which we're basically back in the Stone age. Perhaps we can start to dig a little bit into that. I mean, what would it look like if we had a global nuclear war anytime soon? If there is a nuclear confrontation between, say, the United States and China that in some way also draws in other nuclear powers at the worst case scenario is that the end of humanity, Is that the end of our technological civilization? What would that mean for the planet and for humans?

[Mark Lynas]

Yes, I mean, I'm a student of mass extinctions. I've covered them a lot in my book. In terms of the geological, the big five geological mass extinctions that have happened since the Cambrian fight over the last half billion years. And for climate change, at least in the sense that we're currently experiencing it, yes, there's 100% probability of climate change because it's already happening, whereas nuclear war can never happen. So, so it's a different thing altogether. But there are no. The kill mechanisms aren't there, to use the mass extinction terminology for climate change, There are many more ways to adapt to slow onset events such as are likely to result from climate impacts. Whereas with nuclear war, the kill mechanisms are very obvious. And it's not just the explosions from the bombs and the blasts and the burning and so on, it's the nuclear winter. And that's really the central kill mechanism which can destroy, certainly destroy civilization, possibly destroy humans as a species, and certainly destroy the majority of life in the biosphere.

[Interviewer]

And I feel like nuclear winter is the kind of term that everybody has probably heard, but that many people will have trouble fully understanding, both in terms of mechanisms that lead to a nuclear winter and then what that would mean. So if you have a significant amount of nuclear weapons deployed between two superpowers in the world, why would that cause a nuclear winter and what would that nuclear winter look like? Tell us some of these gruesome details.

[Mark Lynas]

Yeah, so I mean, India, Pakistan, war with 100 nukes or something wouldn't deliver a planet wide nuclear winter. It would, it would make things slightly cooler for a bit like a large volcano. A major missile exchange between the superpowers would lead to a nuclear winter. If you burn most of the large cities of the northern hemisphere and the mechanism is very well established now, you can see it happening in wildfires and some of the firestorms that have happened in human cities. Hamburg delivered not a nuclear winter, but it did deliver A pyrocumulonimbus, which is these big thunderclouds, which are the mechanism by which soot, which are these dark particles, are transported into the stratosphere, which is above the troposphere where the world's weather happens. So if enough soot is in the stratosphere, then it can't be removed by rain. And actually because it's black, it gets heated up by the sun and gets higher and higher into the stratosphere and essentially becomes a veil which wraps around the earth and prevent sunlight reaching the surface in the same intensity. And if you put enough. And the worst case scenario that's studied in the paper I refer to in my book, which was published in nature food in 2022, has about 150 teragrams of soot. And that's enough to essentially make it fully dark at the planet's surface. And the temperatures go below zero practically worldwide and don't rise above zero in the mid latitudes. Somewhere like Iowa is below zero for about 750 days. I so there are no more harvests and there is no possibility of humans surviving even with stored food supplies in any significant numbers at all. The subsequent nuclear famine that would inevitably result from that.

[Interviewer]

So take us through the stages of this, right? So you have, let's say China and the United States going to nuclear war with each other, having this very significant exchange of nuclear weapons. How many people would die as a direct result of an exchange of nuclear arms? And you know, how many people globally would be likely to survive the ensuing nuclear winter?

[Mark Lynas]

Well, so, so the majority of people survive the initial war, the death toll from, you know, an exchange of say 1500 nukes each, so 3000, say 1 megaton nuclear explosion, just for the sake of argument, that would probably kill between a third of a million and three quarters. Sorry, a third of a billion and three quarters of a billion people. And so the majority of the population is left alive. And if you look at this Nature Food paper, then you have to look at what proportion of the population can survive the ensuing food crisis. And there's actually a table in this paper which goes through all of the country's populations. I think for the United States, 99% die. Some countries it's 100%. But for virtually all countries in the world lose the majority of their populations. And I redid the figures for a world of 8 billion and it's getting close to 7 billion would die in the famine, the nuclear famine, according to these model extrapolations, and that's based on what food might remain and distributing it amongst the population so that the with lifeboat ethics approach, so that whatever the proportion is that can have sufficient calories are able to do that, everyone else then dies.

[Interviewer]

Would there be some way for preparing for this? I mean, if, you know the United States is spending enormous amounts of money on national security, if somebody at the Pentagon took very, very seriously the risk of nuclear war and a nuclear winter, you know, would it in theory be possible to start storing up enough preserved food that the American population would be able to get through that kind of nuclear winter? That's just one of the precautions that humanity should try and implement at that scale. I mean, we can obviously produce all kinds of foodstuffs that sufficiently nourishing and keep for over two years. Even ones that actually storage are not going to be a problem. It's going to be so cold, so you can just store things outside, you know, you can have canned tuna for two years, whatever. The problem is that we haven't done that. Right. But presumably, would it in theory be possible to prepare for a nuclear winter in that way and thereby significantly boost the number of people who would survive it?

[Mark Lynas]

That's an interesting question. It's a bit like terraforming. It's a bit like suddenly you're on an uninhabitable planet and you've got 8 billion people to feed. Or if you're thinking at the level of a single country, maybe a couple hundred million, how do you do that for three years? I guess it's not fully inconceivable that you could store enough foodstuffs or you need to be able to produce food without using photosynthesis. So you need to find other ways of synthesizing fresh food and being able to store the ingredients for that. And it's akin to any kind of sunlight blocking catastrophe. So a supervolcano or a very large asteroid would do the same thing. And so it's a conversation that's worth having. What are survival mechanisms if you want the species to survive? I think Elon Musk's plan of going to Mars is probably the least reliable way of doing this. Earth will still be better than Mars under any plausible scenario.

[Interviewer]

And presumably it's less about figuring out how to grow food during the nuclear winter. It's just about pre producing the food before the nuclear winter and storing in such a way that you have enough reserves to get through the nuclear winter

[Mark Lynas]

well, and you need to be able to stop people who you don't prioritize for survival. Being able to access that or being

[Interviewer]

able to, well, unless you have enough food that people know they're going to get through it. And so all of them, you talk in quite vivid detail about how because there'd be such an extreme famine, you would get these roving gangs and you know, all of this kind of violence that would ensue in people trying to procure the foodstuff that they need. But you know, if over the next 10 years we simply say we up US agricultural production by a certain amount in order to produce all of these vast stores of food that would get us through three years, then you avoid not only the starvation but also the kind of mechanisms that produce the need for that gang warfare, the need for these roaming gangs of people desperately searching for food and using violence and weapons in order to procure it.

[Mark Lynas]

Yes. So you need to be able to obviously maintain and defend mechanisms of centralized political authority. I mean you have to be able to distribute food. I mean, if none of it's being produced independently on farms, then it needs to have just some kind of distribution system that needs to be defensible and it needs to be delivered in a way that obviously you can maintain social stability. How you do that in a freezing world of total darkness for at least several months. I mean, precipitation levels don't return to pre war levels. So it doesn't rain or snow at anything like the same extent and for at least a decade. So it's also a very, very long time. I think it's at the moment inconceivable to store the amount of food that would be required to sustain the current global population.

[Interviewer]

So let's assume that this scheme that I just made up does not work. This huge famine, presumably there's also a lot of people dying from the after effects of radiation and so on throughout this period. What would the level, presumably the medical system would break down? What would the level of illness, pestilence and sickness look like during this nuclear winter?

[Mark Lynas]

Well, I mean, immediately after the bombs there's no triage. I don't think there's any conceivable medical system that can support that level of death and destruction. So everyone who's injured is going to die, particularly if they've got acute radiation sickness. But most of them are dead within a month or two. And after that the radiation is a fairly trivial concern. There might be a couple of percentage points of cancer increase incidence in decades to come, but really that's the least of your problems. So I wouldn't be too worried about radiation so long as you can get People into fallout shelters for a couple of months in the hottest zones initially and keep them alive and well supplied in that scenario. I can't believe I'm talking about how to survive a nuclear war. The whole point is not to have one. But you did ask the question. But yes, so that's actually, I think food is really the big one in this issue.

[Interviewer]

And so if we don't take additional, significantly additional propositions to what it is today. Right. If this happened tomorrow, and we have, as you're saying, up to a billion people die from the direct impact of this nuclear war, and then up to 99%, perhaps more in some places, of a population starving to death in the years after that. Where does that leave humanity? I mean, you know, if this nuclear war happens in 2025, what does the world look like by 2035 and what does it look like by 2055 or 2075? I mean, are we basically back in the stone age, or do you think that enough humans survive with enough knowledge that some of the technology that we've developed over the last thousands of years is there and humanity starts to rebuild? I mean, is this potentially a literal extinction event where humanity just disappears, or is it, you know, an event that, you know, kills the majority of humans, you know, obviously leads to huge devastation in all kinds of ways, but that allows those humans who somehow survive this bottleneck to rebuild something like the civilization we know in the decades and centuries to come?

[Mark Lynas]

Yeah, I think it's the latter. So I don't think anybody foresees this as a total human extinction event. But those humans who survive are living in a devastated biosphere where all of the trappings of civilization, from electricity to Internet connectivity to world trade, will have ceased to function because most of the major countries have been wiped out. So there are. I mean, I'll keep referring to this nature food paper because that's the one that actually quantified the death tolls in different places. I mean, there were some countries that had 0% deaths, I think Argentina, Australia. So countries which have very large land areas produce large amounts of agricultural surplus at the moment for export, which would obviously not be exported and have relatively small populations. So yeah, Argentina, Australia, one or two others. So it's not as if in this scenario everybody dies. But I think the kind of post apocalyptic society is very difficult to visualize. We don't really have many historical analogues, even from famines. I mean, I talk about cannibalism because that's a fairly common occurrence in famines and even in Shipwrecks and plane crashes and things. So it's quite likely that humans would eat each other. And that's the main source of remaining food in years like 2 to 3 to 4. But what happens in a kind of rebuilding scenario, I really have no clue. I mean, humans have rebuilt very successfully from past cataclysms. If you think of the Second World War, I mean, look how quickly Japan and Germany rebuilt after that in cities which were basically just flat ruins. So I think the least likely thing is total human extinction. But it's more possible, obviously, if you have a drastically few humans on the planet in a very devastated biosphere.

[Interviewer]

And obviously there was a lot of deaths in Japan and Germany and World War II, and the Urban landscape was very significantly devastated, but the majority of the population did survive. And so it's sort of hard to know how to extrapolate from a situation with some significant percentage of population died, but most of it is intact, to a situation where, say, 99% of the population dies. And of course, a situation in which the same devastation has happened everywhere else. The devastation of World War II was massive around the world, but it's obviously also very important centers of population and of economic activity that weren't devastated in the same way like the United States. And so here, if we're imagining the devastation is practically everywhere, that would significantly change the situation. You're right to say that it's probably very difficult to know exactly what it would be like. I have a personal question for you that I was wondering about as I was thinking about this, which is, would you rather survive or would you rather die? You know, would you rather die in the initial blast, or would you rather be among the people spending the following years searching and scraping around for food and defending yourself against these roving bands of people who want to steal any other food you might somehow have stored or perhaps be forced, if you want to survive, to join those gangs? You know, I think my instinct is to say I love my life and I enjoy being alive on reserve, but I think it might be more merciful to go on that first second of nuclear blast if you happen to be at the center of it.

[Mark Lynas]

Yes. I mean, if you read Cormac McCarthy's book the Road, that's sort of the conundrum. There is what's left worth living for? I mean, there's this sort of love story between the father and the son. And the father obviously tries to remain alive for the sake of the son, but what kind of world is the son going to be living Within. And it was sort of in the back of my head as I was writing this book. And our parents, I mean, used to say, I'd rather be under the first bomb. And you know, I, having written this book, I can see why. And I think they were probably right. I don't, you know, it would. Having to live, you know, it's sort, I guess the closest panel I can think of is a bit, is Holocaust, you know, the struggle for survival in somewhere like Auschwitz where all morality has gone and you know, the best you can hope for is some kind of degenerate existence where you're desperately scrabbling for food, you know, grains of food on the floor and fighting against other people, grandmothers, children, to, to get. To get to it. So is that a world I want to try and survive within? I'm not really sure it is. No.

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[Interviewer]

okay, so we've done the really gruesome stuff at the beginning of this conversation, actually trying to inform people and think through what this would look like. I think the question now is that's not what any of us want to happen. How do we avoid it? So let's backtrack a couple of steps. Tell us about the history of the development of nuclear weapons and why it is that so far we have been able to avoid nuclear confrontation. You know, there's the famous clock by. I forget what it's called, nuclear scientists, the Doomsday clock. And the Doomsday clock is sort of five minutes to 12 at all times. It's been at five minutes to 12

[Joshua]

for more than five minutes.

[Interviewer]

And we haven't reached doomsday yet. So, you know, why is it that so far we've been able to avoid this really gruesome outcome?

[Mark Lynas]

Yeah. So nuclear weapons are obviously famously developed in the Manhattan Project at the latter stages of the Second World War. And as everyone knows from Oppenheimer and just general knowledge, there was two atomic bombs used in Japan and Hiroshima, Nagasaki. In the 6th and 9th of August 1945, the Americans had more bombs planned. They were planning to drop bombs on Kyoto and other Japanese cities that had been spared from this huge firebombing campaign which had already killed hundreds of thousands of people, including this, that infamous raid in Tokyo. And I think it was March 10th of March 1945, which was the largest Single death toll in any air raid which is bigger than Hiroshima.

[Interviewer]

Yeah, the firebombing of Tokyo actually was more deadly than the nuclear strikes. Right. And it just because so much of the center of Tokyo was wooden houses, you know, it wasn't, I guess, similar to the nuclear winter in that sense. It wasn't the strikes themselves and the bombs themselves that killed most people, for they killed a substantial number. It was just this giant firestorm that resulted.

[Mark Lynas]

And it was designed that way. I mean, the Americans designed their incendiary weapons to cause a firestorm. That was the whole point of it. So they were dropped on a target which was already burning. These were napalm bombs to cause the maximum amount of damage to the particular type of housing that Japan had. And there was a program to wipe out city after city after city night after night after night. And it was believed that that would win the war, which it's arguable the extent to which that delivered earlier Japanese surrender versus the invasion of Soviet troops as well, which was happening at the same time. But you know, the history of nuclear weapons after that time, of course, is that the Soviets got them very quickly due to the, the information that they got from Carl Fuchs, primarily on the Manhattan Project, who was the British spy who was passing from passing secrets to the Russians. So by the 50s you have a, you have an arms race where the Soviets are building up nuclear capabilities as fast as possible. Then you get the Cuban missile crisis in 1962, when I think the world realizes how close it is to nuclear Armageddon. And it actually was, I mean, on Black Saturday, which I think is the 27th of October, I might have got the date wrong, but there was a Soviet sub which was forced to surface by the Americans. I don't know if you know this story, Asha, but it's pretty incredible. And the Americans didn't know that this Soviet sub had a nuclear armed torpedo and they were strafing it and dropping depth charges. And this sub was eventually forced to surface and the captain was about to order a dive and order the firing of this nuclear torpedo at the American Navy which would have started a nuclear war over Cuba. And one of the Soviet, the Soviet signaller got stuck on the conning tower while trying to descend so they could shut the hatches and prepare the dive. And there was a commander who outranked, had a fairly high status and outrank the captain who was able to in that delay read that the American Navy was signaling an apology and cancel the order to fire. It was that close and that was after Kennedy and Khrushchev.

[Interviewer]

So a matter of minutes and a matter of really a coincidence. Amalfi.

[Mark Lynas]

Seconds, seconds, seconds. And you know, Khrushchev and Kennedy had already been desperate to de, escalate by this point. But, you know, matters, facts on the ground were taking, had their own momentum and so, and the Soviets also had missiles, nuclear missiles ready to go in Cuba much earlier than the Americans thought. So if they'd invaded, which the military top brass wanted to do, there would have been nuclear war then too. So there was numerous scenarios with Cuba that the world came very, very close indeed. And of course, there's been many subsequent incidents, whether it's bombs dropping out of planes by accident or accidentally blowing up like that Titan II missile did in 1980, or, you know, false information about, about an incoming strike. And so that, that's what's so dangerous really is inadvertent nuclear war as much as the real thing.

[Interviewer]

How much should the concern be about nuclear proliferation? So you say, obviously the United States was the first country to get the nuclear bomb. The Soviet Union quickly followed. Eventually China exploded the bomb, I believe in the 1960s, if I'm remembering correctly at this point.

[Mark Lynas]

Yeah. And the UK has one earlier as well.

[Interviewer]

Yes, I believe there's some question today about whether the UK is actually physically capable of deploying a nuclear bomb without American assistance, which is rather striking.

[Mark Lynas]

But that's true, and that's a question now with the Trump era. That's a serious question for the uk, which doesn't apply to France, let's say

[Interviewer]

now, India and Pakistan. Israel has never acknowledged to have they have a bomb, but they evidently do. North Korea has nuclear facilities. Iran is trying to develop the nuclear bomb. It appears to be quite close to it. How does the probability of nuclear war increase because of that proliferation?

[Mark Lynas]

That's a really interesting question. And I look at this mathematically, actually in the book. So I mean, the published figure is about 1% for inadvertent nuclear war. So that's the estimated probability each year. And probability isn't, you know, isn't cumulative mathematically. So it's not like 1%, 2% over 100 years. It would be, you know, 100%. But it, but it, you know, if you throw, throw a set of dice, lots of times you're more likely to get a certain outcome than you would do if you're throwing it once. So it is, in that sense it is cumulative. And so the probability over a century of a nuclear war is probably about two thirds of that's Just an inadvertent nuclear war and is higher for intentional nuclear war. So it's a, it's a significant risk over long periods of time, you know, which is more than 50, 50 odds probably. And that's, I think what's, what's so scary is that, you know, any, any single day we're probably not going to have a nuclear war. Every single year we're probably not going to have a nuclear war. But over time the risk in that sense accumulates to a very dangerous level indeed.

[Interviewer]

What is the chance of being able to contain a nuclear war in some kind of way? Obviously the United States deployed two nuclear weapons in Hiroshima and Nagasaki. And since then there hasn't really been use of nuclear arms. Is there some world in which if India and Pakistans war escalates, there's an exchange of one nuclear weapon each and then somehow politicians are able to stop further deployment of nuclear weapons? Or is the existential threat when you know that your adversary is deploying nuclear weapon against you so high that you just immediately need to deploy all of nuclear weapons, you have to try and degrade their ability to continue attacking you such that, you know, once you have nuclear war, it virtually by definition is all out nuclear war.

[Mark Lynas]

Well, it sort of is for the U.S. i mean, the U.S. has a launch on warning posture. So I called the book Six Minutes to Winter because theoretically the US President has six minutes to decide whether to respond to incoming missiles when they're just blips on a radar screen. Which is an obviously an impossibly short window to make a decision about the future, survival or not, of civilization. But the theory has always been and remains that you have to get your ICBMs out of their silos before any of the incoming missiles hit. And obviously that raises the risk of inadvertent nuclear war because you have to trust the technology that the blips are actually real. And there's been several occasions when there's been blips and they've not been real on both sides, both in Russia and the United States. But that suggests that the leaderships, and I think Russia probably has a similar posture, although it's much less clear believe that they need to have a full retaliation to any incoming missile threat. So there isn't. So it's less likely you get two or three missiles exchanged than people back off. I mean, the other way to look at this is through war gaming and there's been lots of exercises where they do tend to escalate because you need to retaliate against an incoming missile, and then you've lost 2 million people and maybe your capital city's being attacked. So then you lease off, you know, you release several hundred and one way or another you get to. You get to the full exchange.

[Interviewer]

What about the distinction between a regional war and a global war? I mean, presumably if this involves the United States in exchange, particularly with Russia or China, that would effectively turn into a global nuclear war relatively quickly. What if it is India and Pakistan or some of those more regional powers? Is there an imaginable scenario where it gets contained to that region of the world? And what would the impact and outcome of that be?

[Mark Lynas]

Yeah, I mean, I looked at the weapons of entries of India or Pakistan recently. I mean, the. The Indian one's just been published in the Bulletin of the Atomic Scient, and they probably got a couple of hundred warheads each. So you can. So I mean, the scenario would be, let's say they destroy each other and they destroy all of their major cities and, you know, several hundred million people die. It would probably deliver enough of a punch to the atmosphere that you'd get a degree or two of cooling for a year or so. So it would be a bit like Mount Pinatubo in 1992 times three. So it would affect global food production. And of course it would be a cataclysmic shock to the world in political and lots of other ways, but it's survivable for the rest of the planet. So a regional nuclear war is a survivable event for sure for the majority of the world's population, obviously, not for the competent powers. And that's different, obviously, from an unsurvivable nuclear war where it's not just the competent powers who are wiped out, but also almost everyone else as well.

[Interviewer]

All right, so what do we do about all of that, you know, beyond thinking about it and scaring ourselves and telling horror stories to our children, if we are inclined to psychologically torture them. What do you think the number one, number two, number three priority is in terms of trying to avert what obviously would be a horrendous outcome?

[Mark Lynas]

I mean, it sounds a bit trite, but we have to start talking about it. At the moment, you feel a little bit ashamed. When I told people I was writing a book about nuclear war, people laugh or they say, that sounds a bit depressing. And God, Mark, can't you start writing about depressing things? Because your last book was on climate. So I think that's one. And you've also got to try to formulate, start to Formulate a sort of grassroots bottom up political pressure. So the kind of movement that's paid huge attention to climate change over the last 15, 20 years and has put it on the agenda to the extent that, I mean, all right, there's a backlash currently going on, but it had to put it on the agenda to the extent that all the major economies are now covered by net zero targets. We have annual cops, Huge amounts of attention are given to the issue. None of that happens with, with, with, with nuclear, nuclear risk. There's, I mean, there are, there's annual meetings of the Treaty on the Prohibition of nuclear weapons TPNW, which I think came into force in 2021. You know, and this is a treaty that's been signed by half the world, more than 90 countries, ratified by over 70, and most people don't even know it exists. You know, I talk to audiences about this. No hands go up when I talk about the tpnw. But I think it's important because there is a legal mechanism at the United nations level for the full abolition of nuclear weapons. And I think there are mechanisms within the TPNW as well to begin to up the pressure on nuclear weapons holding states, of which there's only nine, to force them to the negotiating table, to start to get serious again about arms control. But recently the reverse has been happening. All of the arms control treaties, the legacy of the Cold War, have begun to fall apart.

[Interviewer]

How realistic is it that we're ever going to get to complete. Let me do this again. How realistic is it that we're ever going to get to these nuclear powers willingly giving up their arms? There's two concerns here, right? One is obviously that even a superpower that has an ability to defend itself very effectively by conventional means is going to be deeply mistrustful of whether its geopolitical rivals are actually going to be sticking to the same deal, right? So the United States is not at risk of physical attack from China in any meaningful way. Perhaps it's willing to take its chances and say we can defend ourselves with conventional weapons if need be, we can give up on nuclear weapons. But they will say, well, China would obviously dominate us and Russia would dominate us and any power would dominate us if they did have nuclear weapons and we didn't. So if we give up ours and these other powers retain their capacity by cheating, by not adhering to the deal, by somehow being able to delude us about this, then suddenly we are in this incredibly weakened position. And that's a pretty powerful argument for those powers not to be willing to do that. And presumably there's a similar logic for smaller powers. I mean, the reason why places like North Korea and Iran are so invested in their nuclear arsenal is that they feel that that is the defense of last resort against potential attack. That the moment that you have nuclear weapons, that is what protects you against conventional incursions into your territory. And of course, one of the strange ironies about this is that we've made this strange Faustian bargain where the risk of human annihilation, paradoxically, is also one of the reasons why we've had relatively fewer deaths in war, despite the horrible conflicts in Ukraine and the Middle east and so on, than we did for most of humanity, actually, precisely because so many of the major powers are not going to go to war with each other because of this risk of nuclear escalation.

[Mark Lynas]

Yeah, I mean, that latter point, I think, is arguable. I think Russia was emboldened to mount a full invasion of Ukraine in 2022 precisely because it had nuclear weapons and Ukraine didn't. So the existence of nuclear weapons didn't actually prevent war in that they actually made it more likely. And we have to have a situation where humans can carry on fighting wars, but without the biosphere being destroyed. And so even reducing the numbers of nuclear weapons down to, I don't know, maybe 10 or 15 each or something. But then does every country have 10 or 15, or is it still only the current nine? And then if one country has 20 or 50 or 100, then you're back in an arms race. So I think what's crucial here is to abandon any thoughts of unilateralism. I think that's what went wrong with CND and the old peace campaigns back in the 70s and 80s, that the demand for unilateral disarmament was foolish and felt foolish at the time. And that's your only, to use Trump language, that's the only cards that you hold is the offer to disarm your own nuclear weapons if your opponent will do likewise in some kind of verifiable, fully verifiable manner in a sort of stepwise process. And you have to, of course, have full control over all fissile materials and also the civilian nuclear fuel cycle because of proliferation risks, which, you know, the mechanisms, again, all exist for this. This is what the IAEA exists to do and does very successfully everywhere. And that's, of course, why we know the Iranians are going for a bomb by enriching uranium to far higher extent than they ever need to do. For any kind of civilian reactor. And you know how the world responds to that is, you know, the Israelis are more likely to attack Iran because they want to prevent Iran having a, having a weapon, nuclear weapon. And Iran is very likely to go for a nuclear weapon because as with North Korea, it's the ultimate guarantee of regime survival. So something's going to happen. Both those positions can't hold indefinitely. Something will give. But at the same time we also have to not forget the long term ambition of getting to what I call global zero, because that's the only way that human civilization will survive long term. And by long term I mean decades and centuries hence.

[Interviewer]

Yeah, and it's important to distinguish your position from the one of unilateral disarmament, which obviously seems unrealistic. Right. I mean, when you have serious geopolitical rivals who do have the nuclear bomb, to say we are just on our own going to disarm ourselves weakens your position in a way that very few leaders are going to be willing to do and very few electorates are going to be willing to support within democratic countries. To say we're going to try and reach some kind of global deal where we're all disarming at the same time obviously still involves those nuclear 9 weakening the position relative to other countries compared to a status quo, but it's perhaps more imaginable. What are the prospects of some form of global agreement? I mean, it feels to me that two things are going on at the same time, at least in my thinking about this topic relative to 10 or 20 years ago. One is that we seem to be in a more conflictual world with leaders who are more self interest and more assertive and less concerned about global goods like safety against nuclear power than we were a number of decades ago. It would be somewhat easier to see the cast of leaders 20 or 30 years ago making that kind of deal than it is to imagine the current cast of leaders. So the prospects for global zero seem to me to be lower even than they were 20 or 30 years ago. I mean, at the same time, inversely, it also seems to me that the underlying risk is higher then I would have assessed it to be a few decades ago. The risk was always there, it was always real. You talk very compellingly about how close we came to the Cuban missile crisis and so on, but I at least had some kind of sense growing up in the coming to political consciousness as a teenager in the 90s and then as a student and so on in the 2000s that there was some basic rationality to the world. That in the end political leaders made rightly irrational decisions, they didn't want to destroy the world. That in the end we had mechanisms to prevent the worst case outcomes, that we'd worried about a global pandemic breaking out for a long time, but every time that there was talk about how this or that virus might be turning to global pandemic, we had public health authorities do an effective job of stopping that from doing. And I think it made it very easy to sort of assume that yes,

[Joshua]

we need to think about all of

[Interviewer]

these risks, but in the end we have these rational systems that are somehow going to contain these risks and things are going to be fine. In part because of the pandemic, in part because of how erratic some major world leaders now are, in part because of the extent of war that has increased in the last years, such as in Ukraine. I'm sort of less sanguine on that. Right. It's always tempting to think if some horrible outcome hasn't happened, perhaps it can't happen. But that is, I think, intellectually wrong. And it feels like the preconditions for really catastrophic outcome are higher now than were a few decades ago in those areas as well. But that's a pretty depressing outcome. Right, where we're saying the prospects of getting to global zero are lower than were in the past. The risk, or at least our understanding of a risk, is more severe because some of those seemingly rational systems turn out not to be all of that rational. Is it possible to remain hopeful in that situation?

[Mark Lynas]

Obviously difficult to imagine to visualize something for which there is no substantial political constituency, no demand. But that's why I use the analogy of climate change, because I'm around, I've been around long enough and campaigning on that issue to remember what it was like when no one gave a toss and when EVs were milk floats. They were just a joke. Solar panels cost $10,000 per square inch. And it was inconceivable that modern human industrial civilization could function without fossil fuels. And we were heading towards a world of 5, 6 degrees. And again, a catastrophic outcome. We're not in that world now. We're fully committed, I think now to a clean energy transition. It's going to take a long time and we're going to get plus two degrees. And it's going to be a very challenging few decades to come on the climate front alone. But that change came about both for technological and for political reasons. And I think the technologies and the politics are intertwined in that sense. And the economics too. But I think the politics comes first. We have to have a significant political demand, at least in democratic countries, for a de escalation of nuclear risk. And that's not there at the moment. And it's something that we need to organize, whoever we is. And I've tried to do my part to raise attention to it and to help to some small extent put it to put it back on the agenda. And I just hope now that sufficient people realize that it's so the risk is still there. I mean, people had gone off nuclear winter thinking it was debunked and so on. It's not. And that's, I think, why it's difficult for us to imagine a world without nuclear weapons, because nobody's currently asking for it.

[Joshua]

Thank you so much for listening to this not exactly upbeat, but I think really informative conversation. In the rest of today's episode, Mark and I talk about climate change and it is a little bit more optimistic because even though Mark was very, very concerned about the existential risks from climate change in the past and remains very worried about the significantly adverse effect it likely will have on humanity, he has become more optimistic that we're going to be able to avoid the worst case scenarios to keep warming to a concerning 2 or 3 degrees rather than a catastrophic 6 degrees. We talk about why that is, how both political steps and technological innovations have made a genuine difference in the fight against climate change, why we need all kinds of renewable technologies, including, perhaps ironically given the rest of this conversation, nuclear power, in order to deliver the energy abundance we should enjoy as humans. For all of this part of the conversation, please support the podcast. Please become a paying subscriber, Please go to yashamonk.substack.com. Thank you so much for listening to the Good Fight. Lots of listeners have been spreading the word about this show. If you two have been enjoying the podcast, please be like them.

[Interviewer]

Rate the show on itunes, tell your

[Joshua]

friends all about it, share it on Facebook or Twitter. And finally, please mail suggestions for great guests or comments about the show to goodfightpodmail.com that's goodfightpodgmail.com

[Mark Lynas]

this recording carries a Creative Commons 4.0 International License. Thanks to Silent Partner for their song Chess Pieces.