Back in the first half of the eighties, when the Soviet leadership was old, dementing and increasingly paranoid and president Reagan spoke of a winnable nuclear war and set in motion the Star Wars project to make it so, the nuclear holocaust was on many people's minds. It not only featured frequently in popular culture, but several films were made as explicit warnings of what a nuclear war would really be like. Of these movies, Threads
(1984) was the most realistic and scary. The full movie is now available on Youtube
for your "enjoyment". Warning: not very nice, sort of depressing.
The American equivalent, The Day After
(1983, full movie youtube link) was less scary, less honest but still reportedly bad enough to scare Reagan when he saw it in a private showing in the White House.
Raymond Briggs was better known for his gentle Christmas fairy tale The Snowman
but while When the Wind Blows
(182/86) was animated in the same style, it was far from gentle.
For more British cheerfullness, The War Game
) was a 1965 pseudodocumentary about the effects of a nuclear attack on the United Kingdom. It was supposed to have been shown on television on the twentieth anniversary of the bombing of Hiroshima, but had been "judged by the BBC to be too horrifying for the medium of broadcasting" (Wikipedia
For the obligatory Canadian take on things, there's Countdown to Looking Glass
(1984), about the leadup to a nuclear war during a crisis in the Persian Gulf.
More, much more can be found at the list of nuclear holocaust fiction
on Wikipedia. Think of it as escapism: whatever problems you have, at least you're not dying of radiation sickness in a post-apocalyptic world.
That these movies were almost all released around 1983/84 is no coincidence, as that was the height of the new Cold War, after the 1970ties detente. It may have also been the period in which we came closest to seeing a nuclear war become reality, when the Soviet leadership was paranoid enough to think the NATO exercise Able Archer
was a cover for a planned attack and made steps for a first strike. (Previously, 2009