I think that has been a reasonable possibility (on the order of large asteroid collision) since the invention of the atomic bomb. And it became much more likely after they were actually used in war. And even more likely with the insane proliferation. Now we can add climate denialism and global climate state tipping points into the mix. It's getting worse. An opinion shared by the Bulletin of the Atomic Scientists.
"The [doomsday clock]'s original setting in 1947 was seven minutes to midnight. It has since been set backward eight times and forward 16 times for a total of 24, the farthest from midnight being 17 minutes in 1991, and the nearest being 100 seconds, from 2020 to the present."
If someone tells you that we’re closer to nuclear doom now than during the Cuban Missile Crisis, I don’t think you should take their analysis particularly seriously.
I believe the claim is that all risks combined now are slightly greater than the average nuclear risk during the 1953-1960 period.
Regarding the Cuban Missile Crisis in particular, the Wikipedia page says:
> The closest nuclear war threat, the Cuban Missile Crisis in 1962, reached crisis, climax, and resolution before the Clock could be set to reflect that possible doomsday.[citation needed]
"The [doomsday clock]'s original setting in 1947 was seven minutes to midnight. It has since been set backward eight times and forward 16 times for a total of 24, the farthest from midnight being 17 minutes in 1991, and the nearest being 100 seconds, from 2020 to the present."
[doomsday clock]: https://en.wikipedia.org/wiki/Doomsday_Clock