On May 21, 1956, a B-52 bomber dropped a 3.8-megaton hydrogen bomb over Namu Island in the Bikini Atoll. This was the first “airdrop” of a thermonuclear device, and the first time the press was invited to observe a nuclear detonation.*

The following Sunday night, Ed Sullivan, whose weekly variety show was then a national institution, decided to mark the event by presenting an animated film called A Short Vision, a scary imagining of what a nuclear apocalypse might look like. The six-minute film, created by artists Joan and Peter Foldes, had been screened for Sullivan on a trip to London. Although not in the habit of presenting experimental art pieces, Ed must have been excited by the idea of combining an act of social conscience with a sensational atomic horror show. After trotting out the standard guests (portly singer Kate Smith, ventriloquist Señor Wences), Sullivan introduced the film, advising parents to tell the “youngsters in the living room … not to be alarmed.” “It is grim,” he warned, “but I think we can all stand it to realize that, in war, there is no winner.” As it turned out, Ed underestimated the traumatic effect the film would have on children across the nation.

Narrated by British actor James McKechnie and with a chilling sci-fi score by Mátyás Seiber, A Short Vision starts out with scenes of forest animals—a leopard, a deer, an owl, a rat—scrambling for cover after spying a UFO hovering in the night sky. As the ship flies over the city, we zoom in on an ordinary family sound asleep in their beds. We see the lined faces of elder statesmen. The narrator explains: “ … their leaders looked up; and their wise men looked up … but it was too late.”

Above the city, we see a huge explosion, a fireball, a mushroom cloud. And one by one, the faces of the people below begin to change. First, the mouth opens in a silent scream. Eyes open wide just before they liquify and trickle down the cheeks. Then the face melts away, layer by layer, until only the shrieking skull is left. Finally, the skull itself shatters and breaks apart, leaving nothing. The expressionistic, no-frills style of the animation somehow amplifies the horror.

I was 8 years old. Up to that point, the most frightening thing I’d been exposed to was the scene in Thief of Bagdad where Sabu fights a gigantic spider. I knew that was make-believe. This was something else. At school the next day, girls who had seen the film were still in tears. Newspapers ran headlines like this one, on an Associated Press story:

SULLIVAN SHOCKER SETS OFF REACTION

Or this one in the New York World-Telegram and Sun:

SHOCK WAVE FROM A-BOMB FILM ROCKS NATION’S TV AUDIENCE

The Cold War–obsessed website CONELRAD Adjacent, the most detailed chronicler of the airing of the film, features a special page where “A Short Vision veterans” can reminisce about that Sunday evening and, in some cases, tell how it affected their lives. One friend my age told me that he remembers it only as a horrible dream.

Parents and pundits argued about Sullivan’s decision to air the film. As for Ed, he realized he’d struck a nerve. On June 10, he ran the film again, albeit with a stronger admonition to take the youngsters out of the room.

In truth, A Short Vision was only the latest in a series of attempts to prepare the nation’s children for World War III. In 1951, two years after the Russians conducted their first bomb test, President Truman created the Federal Civil Defense Administration. It was the FCDA that funded the famously risible “Duck and Cover” film that was shown to schoolchildren nationwide. In a cartoon segment, Bert the Turtle knows to duck inside his shell when danger threatens. In the live-action segments, we see kids quickly responding to the initial atomic flash, some hastening to crouch under their school desks, others wrapping themselves in a picnic blanket, and so on.

“Here’s Tony going to his Cub Scout meeting. Tony knows the bomb can go off any time of the year, day or night. He is ready for it.” [There’s a burst of white; Tony ditches his bike and sort of drapes himself on the curb.] “Duck and cover! That a-boy Tony! That flash means act fast!”

We really had no choice but to believe that this strategy might actually work. Every day, in the papers, on TV, in FCDA brochures, we were pounded with talk of fission and radioactive fallout. The atmosphere was grim, and most of us were scared shitless. And why not? In 1961, Russia conducted a bomb test U.S. authorities christened “Tsar Bomba” that was 1,400 times the total power of both the Hiroshima and Nagasaki explosions—enough kick to ravage all of North America. Next door, your best pal’s father was stocking his backyard shelter with Tang and Survival Crackers.

I started to read a lot of post-apocalyptic fiction: There was Level Seven, Alas Babylon, A Canticle for Leibowitz. By the time I was 12 or so, I’d become a preteen doomsday prepper. I’d wake up in the morning, look out the window and imagine a colossal mushroom cloud blooming on the horizon. I developed an alter ego, a rugged loner with a plan for survival. I bought one of those Army surplus utility belts and armed myself with a gravity knife, different size screwdrivers, an Allen wrench, plus my Boy Scout mess kit, canteen, and compass. Because, well, you never know what you’re going to need. The unfinished housing development we lived in then provided an excellent post-holocaust landscape. Hell, I’d probably be living underground anyway like a trapdoor spider, at least until the caesium-137 dissipated.

A whole lot of boomers must have had a similar experience, because, a few years later, with a push from oracles like Mailer and Ginsberg, the counterculture was born. There were lots of other factors that led to the anti-establishment subculture of the late ’60s—the post-war obsession with conspicuous consumption, the Kennedy assassination, government distrust, the civil rights movement, the Vietnam War—but our atomic childhoods had ripened us up for the moment. That upside-down “Y” in a circle we all know as the peace sign was originally designed for the U.K’s Campaign for Nuclear Disarmament. The logo uses the flag semaphore symbols for the “N” and “D” of nuclear disarmament. In 1964, Kubrick made us laugh with Dr. Strangelove but, eventually, the nuclear issues seemed to get lost in the chaos of the era.

In recent years, bomb tests by North Korea and the fear that some stateless maniac might acquire an atomic weapon have again put nukes in the news, and maybe that’s not such a bad thing. Should we frighten our children with images of mass destruction? No, duh. But the unthinkable consequences of nuclear proliferation can’t be filed away along with polio scares and Hula Hoops, as a golden oldie from the fabulous ’50s. Nukes are trending again, big time. The FBI has confirmed that smugglers have been trying to sell radioactive materials to ISIS. Apparently, extremists have tried to break into Pakistan’s nuclear facilities on multiple occasions. Kim Jong Un may look like the blithely jovial guy in the “Gangnam Style” dance video, but he seems to have something more spectacular in mind. On Oct. 3, Reuters reported that Vladimir Putin, “in response to unfriendly acts by Washington,” was suspending an agreement to clean up Russia’s arsenals of weapons-grade plutonium. A few days later, the Guardian reported that Russia appeared to be moving nuclear-capable missiles within range of U.S. missile defense posts in Poland.

In our time, the chances of a global thermonuclear war may be more remote (I hope), but a fanatic with a suitcase bomb is no less terrifying. We can’t forget that all that fissile stuff is still out there. The principle is still the same: Split the nucleus of an atom, and the glue that literally holds our world together is dissolved. The chain reaction commences, there’s a lovely big bang, and we’re fried by the same force that powers the stars. If the wise men look up, and it’s too late, a hard rain’s gonna fall, baby.

Correction, Oct. 17, 2016: The article originally stated that May 21, 1956, was the first airdrop of a nuclear device. It was the first airdrop of a thermonuclear device. (Return.)