[sewer_bird]

A total extinction event is pretty unlikely: a nuclear war could perhaps end our civilization, but there'd still be folks around, even if their lives were harder. It's believed that we've already as a species gone through a very small population bottleneck, and homo sapiens can probably survive a nuclear war of even the worst kind.

That said, a thousand years is a long time to research a Death Star I suppose.

[Fej]

A total thermonuclear war would crater most of the Earth and irradiate the rest. Such a scenario wouldn't really be survivable. No arable land left.

[goatlover]

No, it wouldn't come close to doing that. It would flatten and burn cities, military bases, and missile silos that were targeted, and irradiate places downwind. But there's much more land that would not be targeted and isn't near those sites.

For example, what would be the reason to nuke the Amazon, the Arctic, or the Himalayas? How much of Africa would be targeted? What percentage of the US Midwest or Siberia do you suppose would actually be irradiated? What about islands in the Pacific? Is Easter Island going to dosed in lethal radiation from fallout tens of thousands of miles away?

[XR0CSWV3h3kZWg]

Why do you believe that? Some quick searches seem to indicate differently.

https://www.quora.com/How-destructive-is-the-worlds-entire-n...

for MAD to work all you need to assure is that you can damage the opponent enough that their power structure will not survive, not to destroy all of their people/land/capital.

[platz]

gamma ray burst

vacuum decay

[Dylan16807]

those are both ridiculously more unlikely than any kind of self-caused extinction

a gamma ray burst probably won't happen even once in our entire galaxy

[platz]

That's fake news.

We are due for a gamma ray burst. https://youtu.be/8HvwNOSnveE

[Dylan16807]

We don't really know if Wolf-Rayet stars can cause GRBs or not. We're only due for one if they actually can.