Journalist Edward Hunter was the first to sound the alarm. “Brain-washing Tactics Force Chinese Into Ranks of Communist Party,” blared his headline in the Miami Daily News in September 1950. In the article, and later in a book, Hunter described how Mao Zedong’s Red Army used terrifying ancient techniques to turn the Chinese people into mindless, Communist automatons. He called this hypnotic process “brainwashing,” a word-for-word translation from xi-nao, the Mandarin words for wash (xi) and brain (nao), and warned about the dangerous applications it could have. The process was meant to “change a mind radically so that its owner becomes a living puppet—a human robot—without the atrocity being visible from the outside.”

It wasn’t the first time fears of Communism and mind control had seeped into the American public. In 1946 the U.S. Chamber of Commerce was so worried about the spread of Communism that it proposed removing liberals, socialists and communists from places like schools, libraries, newspapers and entertainment. Hunter’s inflammatory rhetoric didn’t immediately have a huge impact—until three years into the Korean War, when American prisoners of war began confessing to outlandish crimes.

When he was shot down over Korea and captured in 1952, Colonel Frank Schwable was the highest ranking military officer to meet that fate, and by February 1953, he and other prisoners of war had falsely confessed to using germ warfare against the Koreans, dropping everything from anthrax to the plague on unsuspecting civilians. The American public was shocked, and grew even more so when 5,000 of the 7,200 POWs either petitioned the U.S. government to end the war, or signed confessions of their alleged crimes. The final blow came when 21 American soldiers refused repatriation.

Suddenly the threat of brainwashing was very real, and it was everywhere. The U.S. military denied the charges made in the soldiers’ “confessions,” but couldn’t explain how they’d been coerced to make them. What could explain the behavior of the soldiers besides brainwashing? The idea of mind control flourished in pop culture, with movies like Invasion of the Body Snatchers and The Manchurian Candidate showing people whose minds were wiped and controlled by outside forces. FBI director J. Edgar Hoover referred to thought-control repeatedly in his book Masters of Deceit: The Story of Communism in America and How to Fight It. By 1980 even the American Psychiatric Association had given it credence, including brainwashing under “dissociative disorders” in the Diagnostic and Statistical Manual of Mental Disorders-III. Had Chinese and Soviet Communists really uncovered a machine or method to rewrite men’s minds and supplant their free will?

The short answer is no—but that didn’t stop the U.S. from pouring resources into combatting it.

“The basic problem that brainwashing is designed to address is the question ‘why would anybody become a Communist?’” says Timothy Melley, professor of English at Miami University and author of The Covert Sphere: Secrecy, Fiction, and the National Security State. “[Brainwashing] is a story that we tell to explain something we can’t otherwise explain.”

The term had multiple definitions that changed depending on who used it. For Hunter—who turned out to be an agent in the CIA’s propaganda wing—it was a mystical, Oriental practice that couldn’t be understood or anticipated by the West, Melley says. But for scientists who actually studied the American POWs once they returned from Korea, brainwashing was altogether less mysterious than the readily apparent outcome: The men had been tortured.

Robert Jay Lifton, one of the psychiatrists who worked with the veterans and late studied doctors who aided Nazi war crimes, listed eight criteria for thought reform (the term for brainwashing used by Mao Zedong's communist government). They included things like “milieu control” (having absolute power over the individual’s surroundings) and “confession” (in which individuals are forced to confess to crimes repeatedly, even if they aren’t true). For the American soldiers trapped in the Korean prison camps, brainwashing meant forced standing, deprivation of food and sleep, solitary confinement, and repeated exposure to Communist propaganda.

“There was concern on the part of [the American military] about what had actually happened to [the POWs] and whether they had been manipulated to be [what would later be known as] a ‘Manchurian candidate,’” says Marcia Holmes, a science historian at the University of London’s “Hidden Persuaders” project. “They’re not sleeper agents, they’re just extremely traumatized.”

The early 1950s marked the debut of the military’s studies into psychological torture, and instead of concluding the American soldiers needed rehabilitation, military directors came to a more ominous conclusion: that the men were simply weak. “They became less interested in the fantasy of brainwashing and became worried our men couldn’t stand up to torture,” Holmes says. This resulted in the Survival, Evasion, Resistance, Escape program (SERE), meant to inoculate men against future attempts at psychological torture by using those same torture techniques in their training.

Meanwhile, the American public was still wrapped up in fantasies of hypnotic brainwashing, in part due to the research of pop psychologists like Joost Meerloo and William Sargant. Unlike Lifton and the other researchers hired by the military, these two men portrayed themselves as public intellectuals and drew parallels between brainwashing and tactics used by both American marketers and Communist propagandists. Meerloo believes that “totalitarian societies like Nazi Germany and the Soviet Union or Communist China were in the past, and continue to be, quite successful in their thought-control programs… [and] the more recently available techniques of influence and thought control are more securely based on scientific fact, more potent and more subtle,” writes psychoanalyst Edgar Schein in a 1959 review of Meerloo’s book, The Rape of the Mind: The Psychology of Thought Control—Menticide and Brainwashing.

Psychiatrists, as well as writers like Aldous Huxley, were aided by the dominant theory of the human mind at the time, known as “behaviorism”. Think of Ivan Pavlov’s slobbering dogs, trained to salivate upon hearing a bell, even if they weren’t tempted with food. The basic assumption of behaviorism was that the human mind is a blank slate at birth, and is shaped through social conditioning throughout life. Where Russia had Pavlov, the U.S. had B.F. Skinner, who suggested psychology could help predict and control behavior. Little wonder, then, that the public and the military alike couldn’t let go of brainwashing as a concept for social control.

With this fear of a mind-control weapon still haunting the American psyche, CIA director Allen Dulles authorized a series of psychological experiments using hallucinogens (like LSD) and biological manipulation (like sleep deprivation) to see if brainwashing were possible. The research could then, theoretically, be used in both defensive and offensive programs against the Soviet Union. Project MK-ULTRA began in 1953 and continued in various forms for more than 10 years. When the Watergate scandal broke, fear of discovery led the CIA to destroy most of the evidence of the program. But 20,000 documents were recovered through a Freedom of Information Act request in 1977, filed during a Senate investigation into Project MK-ULTRA. The files revealed the experiments tested drugs (like LSD), sensory deprivation, hypnotism and electroshock on everyone from agency operatives to prostitutes, recovering drug addicts and prisoners—often without their consent.

Despite MK-ULTRA violating ethical norms for human experiments, the legacy of brainwashing experiments continued to live on in U.S. policy. The same methods that had once been used to train American soldiers ended up being used to extract information from terrorists in Abu Ghraib, Iraq and Guantanamo Bay.

“Here, then, is the brief history of brainwashing,” Melley writes in a 2011 paper for Grey Room. “The concept began as an [O]rientalist propaganda fiction created by the CIA to mobilize domestic support for a massive military build-up. This fiction proved so effective that the CIA’s operations directorate believed it and began a furious search for a real mind control weapon. The search resulted not in a miraculous new weapon but a program of simulated brainwashing designed as a prophylactic against enemy mistreatment. This simulation in turn became the real basis for interrogating detainees in the war on terror.”

While few people take seriously the notion of hypnosis-like brainwashing (outside Hollywood films like Zoolander), there are still plenty who see danger in certain kinds of control. Consider the conversations about ISIS and radicalization, in which young people are essentially portrayed as being brainwashed. “Can You Turn a Terrorist Back Into a Citizen? A controversial new program aims to reform homegrown ISIS recruits back into normal young Americans,” proclaims one article in Wired. Or there’s the more provocative headline from Vice: “Inside the Mind-Control Methods the Islamic State Uses to Recruit Teenagers.”

“I think a program of isolation and rigorous conversion still does have a life in our concept of radicalization,” Melley says. But outside those cases related to terrorism it’s mostly used facetiously, he adds.

“The notion of brainwashing, no less than radicalization, often obscure[s] far more than it reveal[s],” write Sarah Marks and Daniel Pick of the Hidden Persuaders project. “Both terms could be a lazy way of refusing to inquire further into individual histories, inviting the assumption that the way people act can be known in advance.”

For now, the only examples of “perfect” brainwashing remain in science-fiction rather than fact. At least until researchers find a way to hack into the network of synapses that comprise the brain.

Editor's note, May 25, 2017: The article previously misstated that Robert Jay Lifton studied Nazi doctors' war crimes before studying American prisoners of war, and that he coined the term "thought reform."