Almost a year ago, a woman accused Tom Hanks of sexually abusing her as a child and began posting reconstructed memories on Twitter. The accounts are disturbing and specific, but incomplete and unproven—something Hanks’ accuser attributes to the trauma-based mind control she believes herself a victim of. Even though (or perhaps, because) her claims remain unverified, the pedophilia allegations were quickly embraced by a group known for up-leveling whisperings of child abuse into full-blown scandal: devotees of the QAnon conspiracy.

Believers in the QAnon conspiracy hold that President Trump is a “brilliant four-dimensional chess player” using the Mueller investigation as a smokescreen to root out the murderous, Satanic, pedophilic deep state. (It’s a Trump-era catchall conspiracy: Pizzagate + Seth Rich + the Illuminati.) Hanks is the QAnon conspiracists' perfect target: A Hollywood A-lister who donates to Democrats and has been shielded from moral censure by monogamy and his preternaturally wholesome dad routine—until now. And QAnon has done what they do best: Trumpet the unconfirmed revelation until suddenly, in the eyes of internet search algorithms at least, Tom Hanks, America’s uncomplicated, unproblematic favorite, is a pedophile.

Cooler heads will remember that Hanks is innocent until proven guilty, and there is scant proof to work with here; yet, somewhere a conspiracy theorist is very pleased that you’re suddenly, automatically feeling a little suspicious. All the debunkings in the world won’t extinguish that initial spark of suspicion, and that’s exactly the point.

Hanks is only the most recent protagonist in a spate of high-profile pedophilia accusations levied by far-right commentators. Many, like Guardians of the Galaxy director James Gunn’s, have been championed by the same citizen sleuths who powered Pizzagate, the unfounded theory that Clinton-linked DC elites ran a child sex-trafficking ring out of a pizzeria. But while crying "pedophile" is a trollish smear many now associate with the digital wing of the American extreme right, the tactic isn’t native to a particular ideology, and long, long predates the internet.

Alleging that your enemy preys upon children is an ancient propaganda tool that’s been used by everyone from medieval Catholics to the Soviet Union. It’s a powerful indictment because it trades on fundamental human fears. It’s designed to otherize the opposition and sabotage any sympathy you might have for them. It’s a ubiquitous tactic because it works.

It’s easy to piece together how this strategy emerged: Someone figured out which crime their society viewed as most morally reprehensible and went with that—the unforgivable act that almost always involves kids. “Children represent the most sacred ideals any society can have,” says Margaret Peacock, a historian at the University of Alabama who has written about the role children play in propaganda. “They represent the future.” Because humans are biologically wired to protect their offspring, painting your enemy as a defiler of innocence and a threat to the next generation instantly dehumanizes them. And because many societies see pedophiles as not just monstrous but irredeemably so, this charge provides endless opportunities to justify mistreating the group accused of it.

Establishing your opposition as a subhuman beast has been justification for the harshest forms of retaliation. Throughout the 19th and 20th centuries, European Jews were accused of kidnapping Christian children to use their blood in religious rituals; Also throughout the 19th and mid-20th centuries, European Jews were the victims of pogroms and the Holocaust. Where false pedophilia charges go, genocide and repression follow. (A related strategy: Far-right commentators such as Ann Coulter have accused refugees of preying upon children as a way to justify not aiding these groups as they flee deadly, oppressive situations.)

Barely a decade later, the threat of child predation helped rationalize the Cold War, on both sides. The Soviet Union condemned capitalism by suggesting that the US was so reluctant to use social services that its children were forced into lives of crime and prostitution. Over in the US, communism was the real thief of childhood, transforming children into brainwashed robots capable of turning their own parents over to the state for crimes such as hoarding grain. There’s likely some truth to these tales on either side, which is why propagandists chose them: Keeping the focus on mistreated children keeps people from wondering about whether they’re wholly true. The anger stirred by these stories helped keep millions and millions of people on the brink of nuclear destruction because the consequences of allowing the other side to remain unchecked was unthinkable.

In the US, the marches of the civil rights movement occurred alongside a steady drip of propaganda painting black men as a sexual threat to white women and children. “It was as a tool for the othering of the black man, excusing brutal suppression and surveillance,” Peacock says. “It’s arguably helped lead to the rise of the police state they’ve come to live in today.” For the same reason, attempts to criminalize homosexuality (or block marriage equality) have also come along with accusations of pedophilia. Proving these suspicions would require elevated levels of domestic surveillance—unwarranted searches, wiretaps—but stoking fears to produce hate has a way of prompting people to let civil rights slide.

Fortunately, those efforts didn’t pan out. But accusations don’t fade easily. Jews are still charged with mixing children’s blood into matzos. Brainwashed Russian children are still a common trope in US cinema. Stories of predatory black men resurface every time a police officer shoots an unarmed civilian. The myth of the LGBTQ child predator lurks behind every bathroom bill.

In part, the digital far-right’s pedophila obsession is a way of justifying unsavory sleuthing techniques. Everyone lives within the social media panopticon, but doxing and harassment are generally frowned upon. That is, until teams of “citizen journalists” start finding secrets in those years-old tweets. When the ends expose anathema, the means don’t matter any more. And if your audience is looking for an excuse to cement vague feelings of dislike and mistrust, they will readily believe whatever dark deeds can be found in that Instagram photo taken 102 weeks ago.

But also, QAnon believers are holding up the “allegedly pedophilic other” to justify their own existence. The digital far-right has serious PR problems. After directing harassment campaigns against the teenage survivors of the Parkland shooting, it’s hard to argue their concerns are high-minded. With President Trump in office, they’re not underdogs anymore. Remember, the Pizzagate conspiracy sparked into existence just a month after Hillary Clinton called Trump’s supporters “a basket of deplorables.” Pizzagate was formed in direct conversation with Clinton: We may be deplorables, but we’re not pedophiles—you are. And if we post enough, tweet enough, make enough YouTube videos making the same claim, search algorithms will link your name to pedophilia—forever. That’s what happened to Tom Hanks.

As these fringe movements find sympathy harder to come by, they’ll play the pedophile card even more frequently. Smearing public embodiments of the system that rejects them—journalists, Hollywood, Trump-opposing politicians like Senator John McCain—is one of the only moves they have left. Too bad it’s an effective one.

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