Nuclear war is unlikely to cause human extinction

Thanks Alex! Yeah, I agree with you that adding approximate numbers or likelihood ratios would improve this, as would comparing my credences with Toby Ord's. I might do a followup post with some of this if I get time. Originally I was going to find a co-author and go in more depth on some of these things, especially the nuclear winter literature, but I keep starting and not finishing posts and I figured it was finally time to just put up what I had.

It would be good to separate "kill everyone with acute radiation right away" and "kill everyone with radiation in all of the food/water". I discussed risk of the first one and basically didn't at all cover risk of the second one, but I'd like to see a better assessment of the second. I've never found good sources for these kinds of long term effects of radiation from food and water after a nuclear war, despite spending probably 4-8 hours searching. On Thermonuclear War discusses this in depth but it's very out of date (1960), and I haven't found anything like a comprehensive analysis of this anywhere else. Lots of speculation here and there but nothing that looks rigorous.

Thanks for your feedback!

Nuclear war is unlikely to cause human extinction

Yeah, the point that risks from nuclear war would be coupled with risks from great power conflict is a good one. I expect this to be more of a problem in the future, but there could be some risks at present from secret bioweapon systems or other kinds of WMDs. 

My mainline expectation is that in a nuclear war scenario, chemical, biological, and conventional weapon effects would be dwarfed by the effects from nuclear weapons. This is based on my understanding of the major powers deterrence strategy, but might be wrong if there are secret weapons I'm not aware of. The logic of deterrence makes this a little less likely, fortunately. The whole point of a deterrent is lost if you keep it a secret. Of course it's possible that it's kept secret from the public but not from other countries, but this seems harder to keep secret, especially since it relies on one's potential enemies to keep it secret.

Nuclear war is unlikely to cause human extinction

Yeah, you're right I'm making an assumption that a "nuclear war" refers to a nuclear war scenario with current arsenals or those in the near future.

1) Future nuclear weapons, especially if they're designed to kill everyone, could greatly increase the risk. Poseidon / Status-6 aside, I don't think states are likely to invest in omnicide capabilities, for several reasons. One is that it's a really hard optimization problem, and it's easier to be able to just crush your enemy with standard hydrogen bombs. So why pay far more for something that doesn't provide much additional deterrence capability? The other is that it's staggeringly unethical, in such an obvious way that people in most cultures are going to shy away from it. I can see how someone could justify standard nuclear deterrence. But a doomsday device would be bargaining away literally the entire world and future for one's own country, and even then it's a poor bargain. There are some who would contemplate this, but I think their number is relatively small. The fact that such ideas have so far not caught on in a serious way in any nuclear power that we're aware of is a good sign.

2) Very cheap weapons would be bad, agreed. I still think it would be hard to kill everyone with them, but it would at least increase the risk. And if they were continuously build and used, I could imagine longterm effects building up to greater systemic extinction risk.

3) Yeah, these seem like under-explored risks as well, though they don't appear to have much deterrence value so I don't expect military establishments to take them very seriously.

Nuclear war is unlikely to cause human extinction

I really don't think fossil fuel depletion is very likely to permanently curtail humanity's potential in a nuclear or other collapse situation. I've seen this point argued a bunch though, so I think it's worth taking the hypothesis seriously. I'd love to see an in depth analysis of this question.

Nuclear war is unlikely to cause human extinction

Good point re Australia hosting missile tracking capabilities, I agree that it might be targeted given that. I'm less worried about carrier groups and such things being hit. I don't disagree that some of these might be hit, and this may result in some fallout in the southern hemisphere, it doesn't seem like enough to move the dial. The ocean has a lot of area.

I didn't cover sterilization or birth defects from either the initial fallout or from ingested radionuclides later on. These are both problems, but I would be quite surprised if they killed a large percentage of people's children or grandchildren in places not near places hit with a nuclear attack. If you have a source for a good assessment of this, I'd be quite interested. The best I have seen is in On Thermonuclear War and we know a lot more about radiation than we did back then. 

In a future post I want to discuss how long term effects from various technologies, disasters, weapon systems, etc. could combine to lower the habitability of earth. I certainly think nuclear war could play a big role in this, but not cause extinction without other significant factors.

I don't think I agree that nuclear war planners would use nuclear winter effects offensively. A lot of effort in nuclear war planning goes into counterforce targeting, which is explicitly to reduce the effectiveness of the enemy's retaliatory (or reserve / 3rd wave) nuclear strike. This suggests some priority to limiting damage to one's own side. My impression is that the "mutual suicide pact" approach to deterrence is less popular than it used to be.

How useful would it be to have high quality audio recordings of rationality writings?

Was the quality not up to par? If the reading / recording was good, it's surprising that it's not up on

How useful would it be to have high quality audio recordings of rationality writings?

Oh cool, I didn't know about this / or had forgotten about it! I will add this to my podcast feed now. :)

How useful would it be to have high quality audio recordings of rationality writings?

I would be very excited about this. I'm constantly looking for more high quality (both from a content-level and sound-level) audio content. Good readers really go a long way towards creating a pleasant listening experience, so I also would be excited about people skilling up in this area within our community.

My guess is that most lesswrong members don't listen to much audio content, but that a substantial minority listen to a lot of audio content. I expect for this group, more audio content would be quite high value. I also expect the majority group to underrate the importance of this if they haven't spoken with many people in the smaller audio-listening category.

How credible is the theory that COVID19 escaped from a Wuhan Lab?

I think their claim is that labs only (or usually) work with viruses that have been described / that they have published the sequences for. And furthermore that they would have published such GoF work if they had done it (?). Like I said, not very compelling claims, especially because they're general and unclear.

Editor Mini-Guide

I followed Google to this post via Googling: "how to include images in lesswrong posts"

Based on the advice, I tried to upload my photo to Google Drive and share it, but it looks like Google Drive doesn't support this kind of URL-embeddable sharing anymore, if I understand correctly. Next time I will try Dropbox, but if you could update this post to reflect Google Drive no longer supporting this (if you can confirm this is true), I think that would be helpful to others. Including a link on how to upload then share a link to an image would also save future people time who use the same Google query to find this post.

Load More