A limited nuclear exchange occurs in the world, how many people would have to die for civilization to collapse? With the goverments falling and the economy in ruins.

I need an approximate death toll

Edit: the setting is the modern world a couple years in the future.

  • $\begingroup$ Well how many people were in said world before the nuclear exchange and what type was it. because just saying a nuclear event happend and we have no informating about what it was like before would be anyones guess. $\endgroup$ Oct 27, 2021 at 1:14
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    $\begingroup$ This is incredibly broad. Could you narrow it down quite a bit. Also, what do you mean by "civilisation collapse" specifically, and why would you think we could put an exact figure on the death-toll? Giving us context of your world, it's economic systems, social systems and the states of political tension would also help. But again, why would you think anyone can put a specific number on it? $\endgroup$ Oct 27, 2021 at 1:18
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    $\begingroup$ It all depends on what is the intended meaning of the phrase civilization collapse... $\endgroup$
    – AlexP
    Oct 27, 2021 at 1:49
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    $\begingroup$ you need to bomb up every single major nation's government. That is a world war, not a "limited exchange" Or else these nations with enough clouts over other, military and economically smaller nations could rebuild the rest $\endgroup$
    – Faito Dayo
    Oct 27, 2021 at 1:56
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    $\begingroup$ There is actually a hard science answer concerning the minimum death toll necessary to cause the collapse of modern civilisation. It was in Scientific American a while ago, go find the study. $\endgroup$
    – Ash
    Oct 27, 2021 at 6:01

2 Answers 2



Society is part human, part infrastructure. You need humans to operate infrastructure, but humans without infrastructure leads to collapse.

The targets

Let’s say the nuclear exchange is limited, so limited that it only radiates the docks, highways, and the airports of major nations; All of which were evacuated.

The results

Coffee mostly comes from over seas in America and Russia, so immediately all the of coffee that many people depend on is gone. I won’t go over all the specifics, but this will occur with a large amount of services, some non essential like specialty food products, some essential like overseas car parts and specialty electronics.

Then there are the places that consume more food or water than they produce, places that get money through tourism and trade. These places will fail and the people will need a way.

People will try to preserve order, but this will eventually breakdown. If lack of infrastructure makes it so the people of Maine can’t interact with the people of Arizona in any meaningful way, why should they stay in the same country? The more infrastructure is destroyed the greater this effect.

If things get so bad that everyone is back to sustenance farming or minor maintenance jobs, currency might collapse also. Why sell something with money, which can’t feed your family, when you could trade for something you actually need? If the central government falls then money could be counterfeited or stolen.

This will cause society collapse without killing anyone.

  • $\begingroup$ Change the target to the electrical system and that will take down society very quickly. A couple of EMP could take out the whole system including all communications in this country. Look at how Texas shut down when the electrical system went down in Feb. Places that are not so dependent on electricity will survive better. $\endgroup$
    – David R
    Oct 27, 2021 at 15:10

90-95% needs to die.

The black death caused 30-60 percent death, wiping out whole villages. This caused huge social upheaval, but didn't destroy civilization.

Plagues, wars, and famine killed 90-95% of the population of native North America. That led to the collapse of most of the larger native civilizations, reducing the people within greatly.

Societies are extremely resilient to loss, even more so with modern tech. So, 7 billion deaths or so should be enough to break most supply chains and send people into ruin.

Modern society is more resilient. We have radios, which are cheap and simple technology that allows long range communication. We have vast stores of food in shops and such which can be shared out to desperate populations, crops to grow and support people, and people are generally proactive in working to survive after devasting disasters. and so will use modern technology to try and survive longer.

You need a lot of people dead to overwhelm that.

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    $\begingroup$ We live in a vastly more interdependent world than Black Death era Europe. A town cut off from the world in the 1300s was inconvenienced. A city cut off from 18-wheelers today falls apart in days, if not weeks. $\endgroup$
    – Daniel B
    Oct 27, 2021 at 1:25
  • $\begingroup$ Modern tech makes us resilient to loss...provided people know how to use it. To destroy cities, all you need to do is eliminate the infrastructure personnel and anyone who could feasibly take over those jobs. While some people take weeks to learn the system, the remainder riot and/or starve $\endgroup$ Oct 27, 2021 at 1:27
  • $\begingroup$ ncbi.nlm.nih.gov/pmc/articles/PMC2496928 after say, Hurricane Katrina, most people responded fairly well, and worked together quite effectively to handle local issues. People are fairly good at responding to disasters, and there's a lot you can do in a city to adapt. You need a lot of key people dead to break that down. $\endgroup$
    – Nepene Nep
    Oct 27, 2021 at 1:31
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    $\begingroup$ @NepeneNep The world population increased ~0.5% between 2019 and 2020. 25.5% is under the age of 15 (source). That suggests about 17% is under 10. I'd say it's generous to assume a world with a maximum age of 10 would have any hope of survival, and that's an 83% fatality rate $\endgroup$ Oct 27, 2021 at 1:35
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    $\begingroup$ @NepeneNep Huge difference when the disaster hits only part of an otherwise wealthy and functional country. An infected pimple on a healthy body is an inconvenience. Sepsis is frequently fatal. $\endgroup$
    – Daniel B
    Oct 27, 2021 at 7:02

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