Epistemic Status: "Thinking out loud" is probably a good way to describe it. I've been researching and thinking about this stuff on and off for the past few days, and this is the best I've got. I haven't vetted it too closely and probably have made some mistakes.

Some people see me as a very risk-averse person. I wouldn't say that. It's more that I'm death-averse. Risks that involve the possibility of death, I'm very averse to, relative to anyone I've ever met or can think of off the top of my head. Risks that don't involve the possibility of death, I think I'm pretty tolerant of. Financially, I start startups and play poker. Not that either of those things are particularly risky. Physically, an example is that I really don't mind the risks of things like getting mugged or breaking my leg.

I remember the first conversation I had with someone about the Ukraine/Russia conflict (other than my girlfriend). It was with my mom. I was talking on the phone with her and I think I said something like "You see what's going on in the Ukraine?". Her response was something like "Ugh don't remind me. Gas prices are going to skyrocket."

That's not where my mind went. My mind went to death. Nuclear bombs are a thing. Escalation of conflict is a thing. Irrationality is a thing. This very well might end up in a nuclear war that ends up killing me. How high is that risk, and is it worth me doing anything to mitigate it?

My initial instinct was a begrudging yes. I place an extremely high value on life. The risk is actually real. It probably is high enough to justify moving. Which really sucks. I just moved to Portland about a month ago. We're just setting in here. It's been amazing. It's the first time in my life I've been able to live in an urban area, which is awesome because I don't drive. And it's the first time in my life I've gotten to choose my location based on where I want to be, not where I have to be, eg. because of a job.

Next, I ran some quick numbers to get a ballpark of where we're at and whether I need to act fast. Suppose that we value life at $10B (1-3 orders of magnitude higher than you probably do). Suppose that there is a 1/10 chance of me dying if the US is attacked and a 0% chance if I move. If there is a 1/1,000 chance of us getting attacked, staying here would cost $1M. 1/10,000 it costs $100k. 1/100,000 it costs $10k. With that initial analysis, it's not immediately clear to me what I should do. Which is a success, I think. I wanted to see if an initial analysis yielded an obvious action. It didn't. Now it's time for a closer look.

The next thing I did is, after spending a little bit of time googling around for stuff and talking it through a bit with a friend, I wrote RFC WWIII. Writing really helps me think, and I thought it'd be good for the community as well. In that post I dove a little bit deeper into things, but didn't really make it much further than my initial analysis. Talking some things through in the comments was pretty helpful though.

Then I came across 80,000 Hours' problem profile on nuclear security. That seems to contain a ton of useful resources and information. I listened to the thing they push the most there, a podcast episode with Daniel Ellsberg.

That significantly changed my view. From what Ellsberg said, it seems quite likely that if there is a nuclear exchange, it will be large enough to trigger a nuclear winter, and if there is a nuclear winter, we'll all end up dead within a year, save for a few people surviving off of fish and seaweed (and wood?!) in New Zealand, living a Hatchet-style life. If those things are true, moving doesn't really do much for you. Plus, the reason I value life so highly is because of the possiblity of life extension and an awesome post-singularity future. But in the scenario where I'm living off of fish and seaweed in New Zealand, the probability of life extension is near zero. Plus the quality of that life is quite low.

But then, to continue this roller coaster, I came across a tweet by Rob Wiblin saying that he is leaving London due to the threat of a nuclear exchange.

After listing all the imaginable nuclear escalation scenarios I've decided to leave London for now.

The lost life expectancy from remaining narrowly outweighs the inconvenience of leaving for me (which isn't so big).

To help calibrate, a 1 in 1000 chance = ~2 weeks life lost.

Rob is a guy who's opinion I have to take seriously. He is the director of research at 80,000 Hours. I only have a limited impression of him, but from what I can tell he seems to have solid epistemics. And he is one of the more informed people on the topic of nuclear security. He did three 3+ hour long interviews of various experts in the field, and seemingly did a bunch of research to prepare for those interviews. And there's probably more that I'm not aware of. Also, major props to Rob for taking ideas seriously, sticking his neck out, and having the courage and altruism to share his position with the world.

Let's try to look at this with a focus on where the cruxes are. One crux is how likely it is that an attack leads to a nuclear winter. What is nuclear winter? I'll let Daniel Ellsberg explain.

Well, that our policy has actually been the threat of an insane action, an action that essentially we now know for the last 35 years has involved killing nearly everyone on earth by the smoke from the burning cities that are planned to be hit in our war plan. And that smoke, we now know on the nuclear winter calculations, would be lofted into the stratosphere, would spread around the world globally. I’m talking now about a war between the U.S. and Russia, where thousands of weapons would be involved. And a few hundred of those weapons on cities which are targeted would be enough to cause smoke that would reduce the sunlight reaching the earth’s surface by about 70%, killing all the harvests worldwide and for a period as a long as a decade.

But that wouldn’t be necessary, killing all the harvests for about a year or even less would exhaust our food supplies, which globally are about 60 days, and nearly everyone would starve to death except for a small fraction, perhaps 1% a little more or less, of humans would survive, in Australia or New Zealand, southern hemisphere is somewhat less affected, eating fish and mollusks. And that could be a sizable number of people. One percent is 70 million people, but 99% gone and virtually all the larger animals other than humans. They’re not as adaptable as we are, and they can’t move thousands of miles and wear clothes, light fires, have houses. They would go extinct altogether, as they did when an asteroid hit the earth 67 or 65 million years ago and created a very similar effect, blotting out the sunlight by the dust that was sent up.

If an attack leads to such a scenario, it looks like I'll be dead within a year. In which case dying immediately from the attack in Portland vs escaping to Greenland but dying a year later as the crops all fail, it's not like escaping to Greenland gets me a much better outcome.

Actually, it's probably a worse outcome. As much as I don't want to die, I am a believer that there are outcomes worse than death, and a post apocolyptic life in Greenland dreading my inevitable doom as the crops slowly fail, I shiver just thinking about it. It's probably worse than being dead. So that option isn't looking very good.

Similar story with moving to New Zealand in hopes of being one of the survivors in this nuclear winter scenario. I feel like there's a good chance I wouldn't survive anyway even if I did make it there. In a different 80,000 Hours podcast episode with David Denkenberger, they talked about how New Zealand is probably overrated. There's a risk that people fight over a limited food supply and things basically get too crazy and don't work out.

But even if I did survive, that Hatchet-style life doesn't sound very good. It probably isn't worse than dying, but it'd be pretty bad. Let's just say 20% as good as normal life. Suppose we use the typical $10M to value normal life (life extension won't happen in this scenario). That means this New Zealand life would be worth $2M. And let's say, generously, there's only a 50% chance I survive if I make it there. So call it $1M instead of $2M. By moving to New Zealand right now, the logic would be that there is a small chance of losing out on this life valued at $1M. If there is a 1/1,000 chance of being killed in a nuclear attack here in Portland, then staying here is like taking a 1/1,000 chance at losing out on $1M. So an EV of -$1,000. Not worth the hassel of moving. Not even close. Even if it was a 1/100 chance of an attack, the $10k wouldn't be worth it to me either. We'd have to start getting into the 1/10 territory, and I really don't think we're there right now, so it's looking like this is an option that I can shelve for now, and perhaps revisit if things get really crazy.

What a terrible thing to seriously think about though. I really hope I don't have to.

I did say this was a crux though. So far I've been assuming that it is true. But is it? Will a nuclear winter actually happen? Maybe it is only a smaller exchange that doesn't actually lead to a nuclear winter. Ellsberg doesn't think so.

So the war plans of both U.S. and Russia have contemplated as sending not just hundreds but thousands of warheads at each other and hitting hundreds of cities. And something between 100 and 200 cities hit that way, by thermonuclear weapons, would cause this nuclear winter. The likelihood of a limited nuclear war between the U.S. and Russia is not quite zero, but it’s very small. Any armed conflict between U.S. and Russia, which has never occurred yet, would bear a high likelihood or a real risk of erupting and escalating into use or nuclear weapons by one or the other. Once that happened, the change of keeping it limited is very low. Each would worry that the other was about to escalate. And another major point in the book is that our planning on both sides has been aimed, delusionally for this entire period, at limiting damage to one’s own side by counterforce, by hitting the forces of the other side in addition to its cities and its urban industrial centers. In fact, most of the targets on both sides are of military targets, many of them near cities or in the cities actually.

He calls it "not quite zero, but it's very small". That's too bad. He is just one guy though. My experience has slowly been teaching me that seemingly smart people can be wrong, and that I trust them too much. I'd be much more comfortable getting more data points on this. If people in the comments can help, that'd be appreciated.

Something that pushes me closer to the possibility of a smaller nuclear exchange that didn't trigger a nuclear winter is that, it just wouldn't make sense strategically to have a large exchange. Ellsberg actually talks a lot about this throughout the podcast. You can nuke the crap out of all their land based nuclear launch places and stuff, and even cripple their air force so that they can't launch nukes by air, but there are still nuclear submarines. It'd be impossible to disarm all of them. So the enemy would still be able to hit you back with their submarines. Hard. So then, if it doesn't make strategic sense to nuke the crap out of them and start a large exchange, why does Ellsberg think that it is basically inevitable? It's not quite clear to me, actually.

Yeah, I guess I don't understand this very well. In which case, I suppose I should assign something like a 20% probablity of a limited exchange.

In this scenario, I personally would be safe in Portland. I think. From the googling I've done, it looks like it'd be low enough on the list of targets where it wouldn't get hit. The targets are places like military bases, critial infrastructure, government buildings like the Pentagon, and major population centers like New York.

Check this out:

It shows the cities, towns and military sites which will be pulverised in the case of a 500-warhead or 2,000-warhead nuclear attack.

The larger attack, which would target 2,000 locations across the USA, would most likely be an unprovoked attack by an enemy.

In this case the enemy would have the element of surprise and would attempt to hit as many big cities and important military sites as possible.

If America attacks first and is hit as response, the enemy would most likely know a victory would be impossible and would simply attempt to kill as many people as possible.

This map, put together by the Federal Emergency Management Agency (FEMA) and the National Resources Defense Council, shows the areas most likely to be attacked in these scenarios.

The purple triangles indicate big cities, while the black circles are smaller cities and towns, as well as military sites and missile launch sites.

Remember, Ellsberg said it would only take a few hundred nukes to trigger a nuclear winter. And Russia would have to attack a bunch of other NATO countries as well, and the various military bases NATO countries have scattered around the globe. So looking at those purple triangles and thinking about all the other places Russia would have to hit, it doesn't look like Portland would make the cut.

I'm not 100% confident in this though. Maybe I'm... 90% sure? Let's run some numbers on this. Suppose there's a 10% chance that in this scenario, Portland gets hit. In this scenario, it's not guaranteed that I die. I remember reading on some survival blog that something like 50% of people surived in Nagasaki. Looking at these maps of air flow for nuclear fallout, Oregon is one of the best places to be. And looking at this diagram, it looks like if you can manage to get a few miles away from the impact site and stay covered up for 48 hours or so, you're actually in decent shape. So looking at that 50% number for Nagasaki and factoring in that I'm analytical and paranoid enough to perhaps, whether by car, bike or foot, run away from the city center before an attack, maybe the chance I die is something like 20%?

So, we have a 20% chance of a smaller scale attack rather than a larger scale one, 10% chance that Portland gets hit in this scenario, and a 20% chance I die if Portland gets hit. Suppose that in this smaller scale scenario we value life at $2B instead of that $10B I default to, because life extension is less likely. If there is a 1/1,000 chance of an attack in general, then we have an EV of 0.1% * 20% * 10% * 20% * $2B = -$8k.

So, would I live in, say, rural Oregon for a year in exchange for $8k? No, I wouldn't. I like where I'm at. What about for $80k, ie if there was a 1/100 risk? Yeah, I would. So 1/100 seems like the right order of magnitude to target for when I should consider a move. There's also the idea of getting an Airbnb somewhere for a week or so if tensions are particularly high.

What about for people in places like New York? Suppose New York has something like a 80% chance of getting hit instead of Portland's 10% chance. And instead of a 20% chance of dying, it's 40%, because of air flow and nuclear fallout. That's a 8 * 2 = 16 times bigger risk. So I suppose 1/1000 chance of an attack is the order of magnitude I'd target if I lived there.

Let's return to that tweet by Rob Wiblin. He did mention that he doesn't buy the idea of there being no chance of surviving long term, and linked to two podcast episodes he did: one with David Denkenberger and the other with Luisa Rodriguez. Let's explore those and see what we find.

The title of Denkenberger's podcast is "We could feed all 8 billion people through a nuclear winter. Dr David Denkenberger is working to make it practical." The opening quote is:

I’m very concerned that if people don’t know about resilient foods then they could conclude that most people are going to die.

It could be an incentive for countries to do very bad things, like steal food from your neighboring countries.

That’s why I want to get the message out that we could actually feed everyone if we cooperate.

The opening paragraph is:

If there’s a nuclear war followed by nuclear winter, and the sun is blocked out for years, most of us are going to starve, right? Well, currently, probably we would, because humanity hasn’t done much to prevent it. But it turns out that an ounce of forethought might be enough for most people to get the calories they need to survive, even in a future as grim as that one.

The podcast is three hours long and I haven't listened to the whole thing (or read the whole transcript), but it sounds like he's saying that we could do things to prevent starvation in the event of a nuclear winter. I'm not seeing anything about, as things are today, it being likely that we would avoid starvation. In fact, in that opening paragraph, it says that most of us would starve. And looking through the rest of the intro, it seems that if we were to survive, it would mean getting creative with things like mushrooms. That sounds like a pretty bad life to me.

So this isn't helping my estimate of survival in a nuclear winter. In fact, it's hurting it. If nuclear winter was more survivable, I would not expect to see this guy dedicate his career to this and make all of these claims about creative ways to farm mushrooms and the need to extract sugar from wood. I take this as pretty strong evidence that a nuclear winter would be quite hard to survive (which I mostly factored in to my probability estimates above actually, I'm just explaining it in the post here).

There was a section in the podcast that the transcript titled "Should listeners be doing anything to prepare for possible disasters?". I was confused by it. Denkenberger brings up the idea of avoiding popular cities. But he isn't very enthusiastic about it. He does say:

It really depends on how many nuclear weapons are used and whether it’s just the US as the target or all of NATO. But I think that just living on the outskirts of a city is quite a bit lower risk.

But what about nuclear winter? Isn't his whole thing that, as things currently stand, there wouldn't be enough food for people in the event of a nuclear winter, in which case it doesn't matter where you're located? So living on the outskirts would only help in the case of a smaller scale attack. To be charitable, I'll assume that's what he had in mind. I wish he would have mentioned and elaborated on that though. It's a very important question how plausible this smaller scale attack is. Ellsberg called it a "not quite zero" chance. If this is what Denkenberger dedicated his career to, I'd think he'd have spent quite a bit of time thinking about this question. So I'm disappointed to not see more discussion of it.

Let's move to the episode with Luisa Rodriguez. The title of that one is "Luisa Rodriguez on why global catastrophes seem unlikely to kill us all". And yeah, that's what the podcast is about. The idea that not every human would die, and that humanity would slowly build itself back up. Ie. we'd be back to where we are now within 1,000 years.

I don't see how that is relevant though. Or, maybe I should say helpful. I don't see how it is helpful. It sounds like more evidence that we would in fact have almost all of humanity die in a nuclear winter, and the ones who surive would be grasping at straws.

But Luisa has a series of articles on the Effective Altruism forum. Cool! Let's see if there's anything good there.

Opens articles. Skims through them. Wow! The roller coaster continues! Another significant belief update.

Aparently a lot of EAs and people in general just assume that a US-Russia nuclear exchange would result in this nuclear winter we've been talking about that would kill almost everyone. But Luisa doesn't believe that, and her reasoning seems sound.

Let's see what her estimate of an only 11% chance of a nuclear winter would mean. Actually, let's kinda split the difference and assume a 20% chance. She seems more optimistic than other people, and a higher number helps account for the fact that living in a world where a nuclear attack happened but it didn't trigger a nuclear winter wouldn't be as good a world to be a part of. Plus, it's seeming that recent events are evidence against Putin being rational, which I think means a larger exchange is more likely.

Previously I said the following:

So, we have a 20% chance of a smaller scale attack rather than a larger scale one, 10% chance that Portland gets hit in this scenario, and a 20% chance I die if Portland gets hit. Suppose that in this smaller scale scenario we value life at $2B instead of that $10B I default to, because life extension is less likely. If there is a 1/1,000 chance of an attack in general, then we have an EV of 0.1% * 20% * 10% * 20% * $2B = -$8k.

Now we're saying an 80% chance it's a smaller scale attack. So it's 0.1% * 80% * 10% * 20% * $2B = -$32k. Huh. I guess that doesn't change things too much. I previously was giving a 20% chance of a smaller scale attack even though Ellsberg said the chance was "not quite zero" because I've learned not to trust people. Pats self on the back. Thanks Professor Quirrell.

By the way, I'm feeling much better about these probabilities now. Getting another data point is great. Various cool people in the EA community reviewed Rodriguez's work, so it's implicitly even more data points. I like that I've seen, presumably, people on both far ends of the spectrum. Ie. Ellsberg seems close to the end of "it's gonna be a nuclear winter and everyone is gonna die" whereas Rodriguez seems close to the opposite end.

Let's try another adjustment. Rodriguez leans against thinking that an exchange would target cities and instead it'd be military bases. Previously I was assuming a 10% chance that Portland would be hit in this small scale exchange scenario. If feel like I can update away from that. Maybe to 5% instead? Sure. That gives us -$16k. Still in the same vicinity.

I could continue diving into this, but I think this is a good place to stop. Orders of magnitude are what matter. These smaller changes don't matter too much. It seems that a roughly 1/100 chance of an attack is where it'd make sense to relocate for someone like me in a city like Portland. For someone in a city like New York, 1/1,000 seems more appropriate.

Edit: That assumes the super high $2B value on life. Other people probably value it 1-3 orders of magnitude less. I probably shouldn't have used such a high value for myself either. I think I overestimated/didn't really think about the chance of an aligned AI happening in this world where a smaller scale nuclear attack happens. In such a world, it's possible that technological progress is halted, but perhaps more concerningly, I think I'd expect it to be more likely for governments to seek to use AI as a weapon, increasing the chance that it is unaligned. I'll guess that this adds up to a 10x reduction in the value I place on life, so $200M instead of $2B, in which case it'd be 1/10 for Portland, but I could easily be way off.


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Remember the things that ALL have to be true for a "nuclear winter" to happen at all. I'm not gonna say it's a completely debunked myth, but to me the probability is clearly low enough that I mostly ignore it in my planning. Governments have moved on from it too after the initial Soviet politically-motivated hysteria surrounding it during the 80s.

Surviving a full-scale countervalue exchange even within the US or Canada isn't hard. The most crucial thing is to preemptively relocate so you aren't caught and killed in the initial detonation. Anywhere outside an immediate urban boundary is far enough for this. Just make sure you're not adjacent to any other nuclear targets, besides countervalue ones (cities) these include military & important economic/infrastructural targets. E.g. an ICBM silo/base, a major power plant, an important military industrial complex factory, a nuclear waste storage location (ISFSIs may be targeted with groundbursts to generate fallout/denied areas), etc. As long as you can avoid dying in a blast, the other most important elements are:

  1. A good remote location, ideally with easily defendable characteristics. Isolated from large population centres and the chaos and violence being with other people can bring if society collapses.

  2. A large supply of non-perishable food that can be stored and last you for at least 10 years.

  3. Large and varied stock of medications. Not just for personal use to treat the countless diseases, injuries and issues you could develop for years to come but medications will be invaluable as a bartering chip in a post-attack world.

  4. Firearms and ammunition, pretty obvious, for self-defence.

Moving to somewhere like New Zealand may still be nice for the continuity of life, because society and infrastructure there probably wouldn't collapse at all. I mean, why would you expect a simple cessation of international trade to cause a country to collapse internally? There would doubtless be a major economic downturn caused by the loss of large countries overseas but my guess is basic law and order would remain intact.

The Open Source RISOP by David Teter is a good resource for a non-exhaustive but still fairly comprehensive list of possible Russian targets in the US, btw.

That looks excellent! Thank you!

Remember the things that ALL have to be true for a "nuclear winter" to happen at all. I'm not gonna say it's a completely debunked myth, but to me the probability is clearly low enough that I mostly ignore it in my planning. 

It is conjunctive, but I've run probability distributions in a Monte Carlo model in a journal article and got about 20% chance of agricultural collapse given full scale nuclear war. So I think it is important for planning, as the consequences are far larger than the direct effects.

I was about to comment about how nuclear winter may not be as serious threat after reading the first few chapters of "Nuclear War Survival Skills" and then reading through the wikipedia section you linked.

On another note, why do you think 10 years of food, medication, and weapons would be needed when you also say that basic law and order would remain intact?

If there is basic law and order, then food and weapons should not be a hard requirement. I'm estimating that a large part of the population would not survive the initial attack, so food, even without modern fertilizers, should not be that hard to produce, at least in the US with all that rich land. Medication and medication for bartering - this makes sense, since manufacturing would likely take years to rebuild.

I said that about New Zealand (and probably countries outside of NATO, Russia and China in general). Canada may well have law and order intact as well, if we don't get hit or only by a few warheads. I think commercial food availability might be restored before a decade, especially since we have more agricultural production capacity than we need, but it's just to be on the safer side, especially since stockpiling non-perishable food really doesn't cost much. Being so close to the US and sharing a massive border, we may be more destabilized than other non-attacked countries due to things like refugee flood etc.

Bottom line is: if you're in the US, you need all those things I listed prepared in advance for sure. If you're in some non-targeted country you probably don't, but it may still be nice to have them just as a hedge in case of unexpected supply disruptions or upheaval.

But it turns out that an ounce of forethought might be enough for most people to get the calories they need to survive, even in a future as grim as that one.

Some numbers on avoiding starvation:

A case of #10 cans of food, with an estimated 30-year shelf life, from the LDS store, measures 13"x8"x19". Let's say someone buys 50 cases, 10 each of 3 types of beans and 2 types of wheat (this would be 2 orders, as they currently cap at 5 cases of each of those per order). This storage would occupy about 58 cubic feet of one's home, cost roughly $2300, and provide roughly 1230 days of food at 2,000 calories per day. That's around 3.3 person-years of food.

Wheat and beans do not provide for all of one's nutritional needs, nor do these cost estimates include getting a grain mill ($100 - $600 depending on how fancy you want) if you'd rather have flour and bread than porridge. But long-shelf-life food is a buffer to pad out how long you can last on the tastier things that happen to be available in your pantry, freezer, and garden when supply chains go down.

I consider it morally desirable to have a certain runway of caloric independence in case of disaster, because reducing my probable future dependence on limited supplies of humanitarian aid increases the amount of those resources available to those who lacked the resources or ability to prepare.

Genuine question, in the full on nuclear war scenario presumably most people wouldn't have food supplies and just starve. Do you expect to be able to protect your food supplies from organized plundering armed gangs? Eg former criminal gangs, or former police/military?

Do you expect to be able to protect your food supplies from organized plundering armed gangs?

Yes. Compared to most other places, looting my area is unappealingly dangerous and expensive.

In order for a stranger to successfully loot my home, they would have to:

  1. Expend the fuel to travel a long way out into the middle of nowhere
  2. Either loot all the visible homes along the way without getting shot, or coordinate with past looters to know to skip the more dangerous places. If a "skip this house" code starts showing up, you'd better bet we'll all be marking our own driveways with it.
  3. If they're not the first looters, they'll probably have to either repair the main road or risk getting lost and/or stuck in the mud in a maze of logging roads to go around. Or I guess they could walk a few miles. But my community has all the equipment necessary to block the main road in several places, and we'd almost certainly do that if people from town started trying to come out and loot us.
  4. Determine that my driveway is worth investigating, unlike the many similar-looking driveways around here which lead to nothing of value except possibly getting your vehicle stuck in the mud
  5. Clear whatever stuff I've dropped into the driveway, or disembark their vehicles and walk an unknown distance
  6. Figure out where my food is stored
  7. Avoid/disarm any traps, or perhaps perfectly harmless configurations of stuff that look like traps, while searching my property and retrieving my food
  8. Load the food into their vehicles, perhaps by carrying it a fair distance if they didn't want to spend the time or fuel clearing stuff out of my driveway
  9. Safely return to their base of operations without running out of fuel, experiencing a fatal interaction with a neighbor, getting lost or stuck in the woods, etc.

But if there are actually plundering gangs of any sort, having my food stolen would be the least of my worries. I would expect that the kind of lawlessness where groups of "former" criminals are attempting to steal strangers' food would correlate strongly to the kind of lawlessness where people like me get some combination of raped, enslaved, and murdered.

I'd love to see your estimates about why you're resistant to moving to New Zealand.  It's a really nice place!  It can take quite a long time to actually get permission, so figuring out if you should put some effort NOW into opening the option to move at a later date seems worthwhile.

Mobility and options are pretty general instrumental goals.  Like household emergency preparations (food, medicine, first-aid), they are capabilities worth investing in, even (perhaps especially) if you assign low probability to catastrophic insta-death outcomes.

Well, New Zealand specifically, as opposed to some other location that is also unlikely to be attacked, I think the reason to move there would be to protect against a nuclear winter. But the value I came up with in the post for how valuable that is to protect against was only $1,000. And honestly, the more I think about it, the more I think post-nuclear-winter life wouldn't even be worth living.

As for why I prefer where I currently am in Portland to New Zealand, I think a lot of it is practical reasons. I just looked into what living is like in New Zealand and it seems like a great place that has a lot of the things I want! Walkable, moderate/cool temperature, somewhat affordable, and somewhat fun are the main things, and it seems like New Zealand checks all of those boxes.

But it would mean having to find a new job. And from what I understand, programmer salaries are a lot less outside of the US, so that would be a pretty big and easily quantifiable downside, worth somewhere around tens of thousands of dollars a year. It'd also be quite hard to see friends and family in the US in person, due to the travel. If we ignore the inconvenience, it looks like it'd be an extra, maybe $5k/year or something. The time difference I initially figured would be a problem, but it's actually only a three hour difference, so that'd be good!

My girlfriend also wants to be somewhere where weed is legal. I see that it isn't legal recreationally there, and while it is medically legal, this article says "while doctors can prescribe cannabis-based medicines in New Zealand, the program has been criticized as having some of the strictest regulations in the world."

There's also the fact that my girlfriend and I have grown somewhat attached to Portland. We've been excited to move here for a while and finally did it, so having to pick up and leave now would feel like a bummer.

A couple of things that seem to be missing from this analysis is the reliability of the nukes that have not been tested for some 30 years, and might not even explode, since both sides rely on mathematical models to simulate the shelf life of the weapons. What is the chance of the model developers missing one critical factor out of many that go into the calculation? Humans are pretty bad at accounting for unknown unknowns. The other point is focusing on US vs Russia exclusively. China has some 10% nuclear capacity of each, and who knows what they would do if s*** hits the fan. 

Hm, true. My impression is that they'd be pretty likely to explode though, and that each side has enough nukes where even if some didn't explode, they would just use others, and so it is the desire to use a nuke that really matters. And yeah, I think the existence of China (and North Korea) does increase the risk slightly. Neither thing seems large enough to really sway the results I found though.

Russia dismantled all their Soviet-era bombs and used the fissionable material to make new bombs.

The US has probably started to do the same thing, but I don't know how far along it is.

If I learn that Russia has started evacuating her cities, I'd rent a car, drive from where I live in the Bay Area to near the California-Oregon border and construct a temporary fallout shelter according to the instructions in Nuclear War Survival Skills.

The most likely (but not particularly likely)nuclear attack this year would involve only a few weapons, probably only one, by Putin as a way to express his disapproval of the countries supplying Ukraine with weapons, and he would with p = .98 choose to target a non-nuclear country (i.e., not the US, the UK or France) to reduce the probability of nuclear retaliation. One of the documents in the archives the Yeltsin administration opened to Western historians was a Soviet plan for the invasion of Western Europe that began with an attack with dozens of nukes on targets in West Germany, the low countries and northern Italy and maybe a few in Scandinavia (mainly on air bases and a few on military headquarters IIRC) and exactly zero targets in France or Britain.

Of course, in such an attack (the likely scenario), Britain or France (but not the US) might be hit with deadly fallout.

It is unlikely Putin would nuke Ukraine. (He has and will continue to have other options there.)

Thank you so much for writing this. I've had a lot of the same questions myself, and I really wanted to see someone's Fermi estimates on them. This is exactly the kind of thing I was hoping to see.

Glad to hear it was helpful!

And here I thought this was going to be a question about 'what if Russia decides to launch nukes with a target, well, closer to it.'

Isn’t his whole thing that, as things currently stand, there wouldn’t be enough food for people in the event of a nuclear winter, in which case it doesn’t matter where you’re located?

No. "Enough for everyone" is rather different from, say, New Zealand having enough but India not having enough.

Ah, I see. Perhaps he believes that various places like New Zealand will be fine but other places like India will not, and that fact is worth dedicating his career to fixing.