On Towards the Stars: Nukes
[This post is part of a larger strategy guide for Civilization 6]
Nukes are weird. I mean, in the 99% use case, they're pretty straightforward.
bomb goes boom
city gets destroyed
walk some random unit into the wreckage to capture the city
(generally) raze it since it's probably useless now
But nukes have a ton of weird edge cases about how they can be fired and intercepted. And since nukes are, uh…nukes, it’s probably worth knowing how these things actually work.
Basic strategy
Nukes are significantly harder to defend against than they are to make. As a result, by the time nukes come online, you want to either be making a ton of nukes yourself to threaten your enemies, or be pretty sure you have a victory in hand. And if you're behind, it is a totally viable strategy to just try and build as many nukes as possible and send your opponent to the stone age.
Deploying nukes
Deploying even a single nuke is really expensive. You need to research the tech, AND run the Manhattan project, AND build the nuke. And then you need a way to deploy it, which requires an additional tech and a unit.
Assuming you're just rushing to deploy nukes as fast as possible, you should try and do the following:
Put Magnus in your highest production city and upgrade him to get both of his final tier upgrades.
Build as many nearby factories and (coal) powerplants nearby to maximize production in the city with Magnus.
Get through all the nuke techs, possibly by spamming city projects, and run the Manhattan Project in the city with Magnus.
Build a nuke.
Research rocketry to get missile silos.
Have a pre-built military engineer lying around, near an enemy border.
The timing of this will generally vary, depending on how soon the science and production pieces start/finish. The earlier you decide you just want to rush nukes, the easier it will be.
Defending against nukes
I’ll be honest, I didn’t even know you could defend against nukes for the first 1000 hours of playing this game. It’s really hard to pull off, and really rare. But in multiplayer, it’s sometimes the difference between eking out a win or choking in a game that should have been yours, so it’s worth knowing both how to pull off the rare nuke intercept and how to make sure it doesn’t happen to your nukes in particular.
For the most details, I think the civ fandom wiki on air combat has the most comprehensive guide on nuclear interception works. Instead of copying that word for word, I’m just going to link out there. Read it!
While intercepting nukes is an important trick to have in your back pocket, your best bet to avoid being devastated by nukes is to have really wide borders, with a big buffer between an opponent's effective nuke range and your best cities. If you get nuked, you basically always want to nuke back and make the land area on the border impossible to get through1 2.
In terms of broader strategy, in some real sense, if your opponent has nukes and you don't, you're going to have a bad time. Because civ is a game, MAD isn't really as much a thing. Even when everyone has nukes, they tend to be used pretty frequently. So once you get kinda close to the nuke tech you really do want to beeline for it.
But what’s the point of building nukes if they won’t deter people? You build your own less because it will deter enemies, and more to ensure that you won't end up too far behind when your cities come under fire. In other words, you always want to be able to fire a nuke AND take out an opponent city should the same happen to you. That means:
Having the nuke and the means to deploy it…
In range of an enemy city…
With a nearby melee/cavalry unit that can take the city once it is dead.
Great People
Nuclear weapons are one of the only ways to actually kill great people! I’m sad to say I lost a game of civ because I had a bunch of great scientists that all got nuked, setting my space race way back. It’s a small thing, but if you have a late game great person, don't put him directly on the space port or in nearby cities until you know you can use him safely!
Remember, you still keep cities that have been nuked! You only lose them when an opponent's land units manage to get close enough. I’ve sometimes nuked my own territory when I know my opponents have a big army sitting around there. Having a few dead tiles isn’t so bad if it stops a mountain of tanks from steamrolling you.
If you're getting nuked from the sea, it's even more critical to have well thought out counter-nuke attack options, in large part because it's much harder to react quickly.