

11/22/1963 spoiler
Although kinda the opposite, the book 11/22/1963 is about a time traveler who stops the JFK assassination, but then returning to present day, finds the world in ruins because JFK lived and bipartisan/international sympathy over his death never happened, so the cold war escalated to the point of nuclear war, and present day was like the world of Fallout.
Impossible to say, but it’s possible the reverse could be true, and if Regan died, the USSR could have seen an opportunity and attacked, starting mutually assured destruction?
“Jaws was never my scene and i don’t like star wars”
~ Freddie Mercury