This document describes precautions to take in a scenario like the Cuban Missile Crisis, where nuclear war seems plausibly imminent within the next days or weeks. This is not a guide for what to do if a missile is currently inbound and will strike within minutes or hours.
Overview
If tensions between nuclear powers are running extremely high, and you are in or near a plausible target during a nuclear war (such as a major city in the United States or Europe), then I recommend evacuating to a safer place as soon as possible, and staying for days or weeks until things have calmed down. New Zealand is an excellent place to go, or if international travel doesn’t seem justified, then any nearby rural area will probably do fine.
This plan requires that you maintain a valid passport, so that you can leave your country on short notice if needed. No other special preparations are needed.
Proper calibration here should include substantial tolerance for false positives. For people with the means available, I think it was correct to evacuate during the Cuban Missile Crisis, even though it did not end up leading to nuclear war.
Why New Zealand?
New Zealand is of little or no strategic relevance to the current conflicts between nuclear powers. The experts I’ve talked to agree that it’s implausible that anyone would target New Zealand with nuclear weapons, or that anyone would invade New Zealand in the aftermath of a nuclear exchange.
New Zealand is easy to enter. Anyone with no notable criminal history and a valid passport from most countries, including the US, EU, and Canada, can get a New Zealand tourist visa on arrival, with no need for a prior application, and stay for up to 90 days. (Make sure to get a round-trip ticket, or they might not let you in.) Edit 2023: No longer true, New Zealand now requires a “New Zealand Electronic Travel Authority” application which they claim is usually processed in 72 hours. If you’re reading this after 2023, this and other parts of the analysis may be out of date.
New Zealand is a major food exporter. If supply chains are disrupted, you’ll be close to the source.
New Zealand is very stable internally. It has a strong Anglo tradition of governance, reasonable national pride, no coups or civil wars within the last century+, negligible riots or ethnic strife, etc.
New Zealand is culturally familiar. It’s an English-speaking country that’s firmly within Western Civilization. As such, most of my audience will be more comfortable staying there while waiting for tensions to calm down, and will stick out less if there’s chaos or rioting after a war.
No other country is so good on so many of these dimensions.
Backup Plans
If you are unable to enter New Zealand, then there are many other countries which look like good options: many South American countries, Australia, and Botswana. Partial notes here.
If you are unable to leave your country (this is unlikely if you have a valid passport; see below), then you should drive to a small town far from any metropolis or other plausible target. (After brief examination, for people in the Bay Area, I recommend the Modoc Plateau in northeast California as a default unless/until more research is done.) Once there, organize, acquire supplies, and find a location to dig fallout shelters. Construction is described in Nuclear War Survival Skills, the full text of which is online. The book claims untrained civilians can build the shelters in 1-2 days.
Other Concerns
How will I know when to evacuate?
This will probably be obvious. Past diplomatic crises between nuclear powers have frequently been widely publicized.
If I decide to evacuate, I will send a brief alert to anyone who signs up to receive one via this form.
Won’t all the flights get booked due to mass panic?
Probably not, judging by past cases. For example, it looks like there were no large-scale evacuations during the Cuban Missile Crisis, in spite of very alarming headlines. (It seems to me that most people have trouble thinking about nuclear destruction in a way that permits any action whatsoever.)
What about nuclear fallout?
Based on a friend’s analysis, fallout risk in New Zealand is low unless New Zealand itself is targeted, and the experts I’ve talked to agree that this is implausible.
Fallout is dangerous for about two weeks. Nuclear War Survival Skills (full text) describes how to build shelters, which would be uncomfortable but effective.
Ben Landau-Taylor 
After I posted this, some friends reached out to me for further advice, some of which could be useful to others. What follows is a couple conversations that I’m reposting with permission, lightly redacted for privacy:
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X: Is it easy or quick for you to recommend to me where I ought to tell my parents to go? They live 40 minutes north of Chicago. I expect it would be hard to convince them to go to New Zealand because they will think I’m being nuts, but I could easily send them to a small town somewhere driving distance or a short flight, probably in the Midwest. Not sure what criteria you use for determining which areas are best if you are remaining in the country!
Ben: Criteria I’d suggest, in order of importance:
—Distance from major cities, ports, military bases, or other plausible targets
—Practical to drive there in a day or so (driving lets you bring supplies)
—Rural area with low population density, but also agriculture and towns where you can buy supplies
—Ideally you want someplace where fallout won’t be carried on the wind, but this is quite hard to figure out. I’ve been defaulting to “it’s probably good to be on mountains or other very high ground” because I haven’t put in the time to actually understand this.
If you come up with a recommendation, please let me know. It could be good to have default recommendations for various regions.
X: Thank you very much– I will let you know if I come up with a recommendation!
Ben: After 90 seconds looking at a map, my guess is that “Wisconsin far away from the lakes” might be good.
X: It is a bit tricky to find high elevation in the Midwest, at least after 90 seconds of my own….
Ben: Yeah, I suspect there may not be any elevation differences that matter in that region. It’s on my mind because we have a bunch out here.
X: Maybe the Wisconsin Dells? Not too close (I think) to either Minneapolis or Madison but vacation-y so I could maybe convince them…..
Part of my own criteria is I have to be able to frame it as a vacation, unfortunately.
Ben: Looks pretty good. Maybe a bit closer to Madison than is ideal, but not so close that it’s a dire threat, and Madison doesn’t seem like a super likely target anyway.
X: Ok, good to know. Thanks Ben!
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Y: Any thoughts about how one would do while in a plane flying over a nuclear attack? I have a good amount of data on horizontal fallout ranges for different types of weapons, but do you happen to know if the vertical zones are similar?
Ben: I don’t have info on that.
Y: It also sucks that from the east coast of US it’s impossible to get to new zealand unless you fly commercial – range isn’t long enough on private planes, so one would have to refuel somewhere
(max out at about 8,500km)
Ben: If you try to get out days before an attack rather than hours before an attack, I think this ends up being not a huge concern.
Y: With shorter notice one will have to make a decision about going underground vs in the air
Ben: Yes. If the situation is “missiles are literally in the air,” I expect air travel will not be a good option. In most other situations the time to a possible attack will be unknown, and I think air travel (including commercial) makes sense in that circumstance.
Y: hmm… makes sense
NZ is [about 20] hours from [redacted East Coast city]
somewhat unsettling
Ben: I expect there are probably parts of Canada that are more reachable and very far from any plausible target. Possibly worth investigating?
Y: I was just thinking the same thing
Ben: If you do, let me know what you find.
Y: will do
do you or Samo have a read on NZ geopolitical agency?
Ben: My impression is that they’re focused on local matters, and don’t have any exceptional talent that would let them punch above their weight.
Y: got it – any agreements from other countries to defend?
Ben: It’s about what you’d expect. They’re strongly aligned with Australia, and generally aligned with the US via the Commonwealth. They’re not part of NATO de jure; I don’t recall what other formal treaties they may have.
Their military is pretty small. I think the only real relevance they’d have is as a port and airbase near Australia. This is irrelevant for all plausible conflicts except a China-Australia war, which seems unlikely, and if it does happen China has few enough nukes that I doubt they’d prioritize NZ. (Still maybe worth staying outside of the major ports, if this is a concern.)