The greatest pall to hang over the world was the Cold War..
Not for the Russians it wasn't. It's important to note that as far as the Soviets were concerned, the United States posed a far less existential threat than Nazi Germany or even China, the former of which cost them $20 million lives and sacked several of their major cities.
The Americans went through the Cold War with this concept of "Mutually Assured Destruction," the assumption that the Russians could be convinced not to attack the United States because any attempt to do so would cause the total end of their civilization. The Russians never really got that concept; THEIR idea of nuclear war was "Nuke em till they stop shooting back." IOW, in their view getting nuked by the United States was hardly the end of the world; in some ways, it was no worse than what the Nazis did to them decades earlier, except that this time the Russian counterattack would immediately inflict identical damage to the United States and give them time to rebuild.
Have you ever seen interviews of Russian scientists, politicians, generals on documentaries from long after the cold war's end? I have. You've never seen a more extreme group of paranoid delusional people in your life. They thought the US was just as much an evil empire as Reagan thought of them. They really thought the US was planning a first strike! Even down to the day and minute in some cases, when they went on high alert. However, their strategy was an overwhelming first strike. They thought they could win a nuclear war simply by minimizing damage from the US, not by fighting a full blown war. In reality, such a war would have been won by no one, and certainly the clear thinkers on either side realized this.