This is actually still a reasonable concern to have. Coincidentally, just yesterday I came across a reference to the book Nuclear War: A Scenario by Annie Jacobsen, speculating on how a global thermonuclear war could start in modern times.
The scenario she presents is fictional, but it’s all based on current nuclear arsenals and response protocols. While what I’ve read of it certainly makes it seem like a worst-case scenario in a “nearly everything that can go wrong does” sense, it’s disturbing how relatively few things going wrong it actually takes—in a span of under two hours—to reach “civilizational collapse” level outcomes.
https://en.wikipedia.org/wiki/Nuclear_War:_A_Scenario
The scenario she presents is fictional, but it’s all based on current nuclear arsenals and response protocols. While what I’ve read of it certainly makes it seem like a worst-case scenario in a “nearly everything that can go wrong does” sense, it’s disturbing how relatively few things going wrong it actually takes—in a span of under two hours—to reach “civilizational collapse” level outcomes.