A 2022 study, cited by Jacobsen, predicts five billion deaths/ Representative Image
If World War III begins as a burst of missiles and miscalculation, Annie Jacobsen argues, it will not be a protracted campaign but a compressed sequence of decisions and detonations, the kind that could kill, as she explains, referencing a 2022 study, “five of the eight billion on Earth… in the first 72 minutes.” Her new book, Nuclear War: A Scenario, stitches declassified documents, interviews with defence scientists and climate-modelling research into a minute-by-minute reconstruction of how a modern nuclear exchange could unfold, and why only a few remote countries might retain the capacity to feed themselves afterwards.
Why Jacobsen’s scenario deserves attention
Jacobsen is not a speculative blogger. She built her reputation investigating the national-security world: The Pentagon’s Brain (a Pulitzer finalist) examined DARPA and secret defence projects; her reporting has drawn praise from Columbia University’s awards committee as “brilliantly researched.” Nuclear War: A Scenario is labeled a scenario deliberately, it is a fictional timeline, but its building blocks are technical and sourced. That gives the narrative weight: the scenario reads like a ledger of what existing systems, policies and physics would produce under certain pressures.Jacobsen frames the work as an exercise in clarity. No one can know what might trigger an all-out nuclear war, which countries would be involved, or how events would unfold. As the book’s title makes clear, this is just one possible scenario, and her detailed research gives it more credibility than most.
The scenario, in brief: how 72 minutes become apocalyptic
Jacobsen opens her scenario with a surprise: North Korea fires two missiles, an ICBM aimed at the Pentagon and a submarine-launched missile for a US nuclear reactor in California. The political motive is intentionally unspecified; the point is what the launch triggers.Speaking to Politico, Jacobsen notes that the key physics have barely changed since the early Cold War. “It takes 26 minutes and 40 seconds for a ballistic missile to get from a launchpad in Russia to the East Coast of the United States,” she said. That was true when nuclear physicist and Pentagon adviser Herb York first ran the numbers in 1959–60, and it is true now. From North Korea to the US, she adds, “Pyongyang is 33 minutes because it’s a little bit different geographically.”As soon as early-warning systems detect launches, commands circulate. The president is moved to safety and the “nuclear football” is opened. Jacobsen emphasises the time pressure: “Part of the terrifying truth about nuclear war… the president has only six minutes, that’s the rough time to make this decision. And in that time, the Black Book gets opened; he must make a choice from a counterattack list of choices inside the Black Book.” The options, immediate retaliation, limited response, or restraint, must be chosen in minutes. In Jacobsen’s reconstruction the United States orders a broad retaliatory strike: dozens of targets in North Korea and related facilities. American missiles travel over Russian territory. Russian launch officers, seeing inbound warheads and unable to reach US leadership in time, interpret the flights as an attack and respond immediately. Within just over an hour the exchange escalates into multiple states launching warheads; in the book’s worst minute-by-minute accounting, a thousand Russian warheads obliterate large swathes of the US, producing overlapping firestorms and instant mass casualties. Jacobsen describes the opening fireball vividly. On Steven Bartlett’s Diary of a CEO she said the first weapon was “a one mega ton thermonuclear bomb” over the Pentagon, adding: “All sourced from defence department documents, defence scientists who have worked for decades to describe precisely what happens to things and to humans…and it’s horrifying.” She totals the immediate mechanisms: flash, blast, collapse, secondary fires, and prompt radiation. By minute 72, she writes, the immediate death toll reaches into the hundreds of millions. But the longer-term damage, she argues, is worse.Also read: Nuclear war expert explains why Australia and New Zealand may be the last places left standing after WW3
The second catastrophe: nuclear winter and famine
Where Annie Jacobsen’s scenario turns truly bleak is not in the detonations themselves, but in what comes after them. Once the fireballs fade, her narrative moves into the climate science that tries to answer a single question: What happens if dozens of modern cities burn at the same time?She draws heavily on the modelling of Professor Brian Toon and researcher Ryan Heneghan. Their work suggests that vast plumes of soot from city-wide fires could rise high enough to enter the stratosphere, where global winds would spread the particles around the planet. In that layer of the atmosphere, soot does not wash out quickly. It stays, forming a veil that blocks sunlight for years.With sunlight diminished and rainfall patterns disrupted, the world’s major food belts, the American Midwest, parts of China and India, and the grain regions of Ukraine and Russia, suffer catastrophic declines in crop yields. Growing seasons shorten. Temperatures drop. Jacobsen describes fields that normally feed billions becoming “just snow for 10 years.”As she puts it: “Agriculture would fail, and when agriculture fails people just die.”Toon and Heneghan’s models estimate that famine alone could kill around five billion people, not from blast or radiation, but from a planet suddenly unable to grow enough food. Oceans would not provide relief; colder waters and damaged ecosystems would collapse fish stocks. And when countries have no food to trade, global commerce disintegrates. Shipping, insurance, port logistics, the entire system that moves calories around the world, stops functioning.In Jacobsen’s telling, the survivors inherit not a ruined civilisation but the absence of one. She cites Nikita Khrushchev’s old warning that, after nuclear war, “the survivors would envy the dead,” not as melodrama but as a summary of what the science implies.She emphasises that her book lays out a scenario, not a prediction. But the point of sketching it so precisely is clear: nuclear policy is often discussed in abstract phrases, “unacceptable damage,” “second-strike capability,” that obscure the human consequences. By grounding her narrative in existing research and real military procedures, she aims to show, in concrete terms, what a global nuclear exchange would actually mean for the systems we depend on to stay alive.
Why Australia and New Zealand stand out, and what “safe” actually means
One striking line from Jacobsen’s interviews has circulated widely: only two countries could plausibly sustain agriculture at meaningful scale after a full nuclear exchange, Australia and New Zealand. She relays Professor Brian Toon’s assessment in conversation: “Only two countries could potentially survive a nuclear winter,” he told her, “New Zealand and Australia, who can ‘sustain agriculture’.”In Jacobsen’s telling, Australia and New Zealand end up in a comparatively better position mainly because of where they are and what they can produce. Their distance from likely target corridors, the fact that they normally generate agricultural surpluses, and their access to renewable energy and domestic food sources give them an edge if global supply chains collapse. But she also stresses that “safest” doesn’t mean “safe.” Life in the Antipodes after a nuclear war, as she describes it, is still harsh, defined by rationing, living underground, and relying on stripped-down, survival-level agriculture rather than anything close to normality.
What we should take from the scenario
Jacobsen’s exercise is not a call to panic buy bunker supplies. It is a blunt attempt to make policy realities visible. Her minute-by-minute account underscores two linked truths: the physics and timing of modern nuclear arsenals leave almost no slack for error; and, even if a large fraction of humanity survives the initial blasts, the planetary ecological consequences could kill far more in the weeks, months and years that follow.In the scenario, she said, “five of the eight billion on Earth are likely to die.” The line is intended to force both the public and policymakers to confront what deterrence failures, escalation, and miscalculation could actually produce. Jacobsen isn’t claiming certainty, and she isn’t trying to predict how a nuclear crisis would unfold. She uses scenarios to show the kinds of choices people would face and the consequences those choices could trigger. The book keeps circling a simple question: if nuclear war can spiral so quickly and the systems around it are so fragile, why do we rely on the idea that leaders will always stay rational and communication will always work? Go to Source
