WASHINGTON — Days after Maui’s wildfires killed scores of people and destroyed thousands of homes last August, a shocking claim spread with alarming speed on YouTube and TikTok: The blaze on the Hawaiian island was set deliberately, using futuristic energy weapons developed by the U.S. military.

Claims of “evidence” soon emerged: video footage on TikTok showing a beam of blinding white light, too straight to be lightning, zapping a residential neighborhood and sending flames and smoke into the sky. The video was shared many millions of times, amplified by neo-Nazis, anti-government radicals and supporters of the QAnon conspiracy theory, and presented as proof that America’s leaders had turned on the country’s citizens.

“What if Maui was just a practice run?” one woman asked on TikTok. “So that the government can use a direct energy weapon on us?”

The TikTok clip had nothing to do with the Maui fires. It was actually video of an electrical transformer explosion in Chile earlier in the year. But that didn’t stop a TikTok user with a habit of posting conspiracy videos from using the clip to sow more fear and doubt. It was just one of severalsimilarvideos and images doctored and passed off as proof that the wildfires were no accident.

Conspiracy theories have a long history in America, but now they can be fanned around the globe in seconds, amplified by social media, further eroding truth with a newfound destructive force.

With the United States and many other nations facing big elections in 2024, , the perils of rapidly spreading disinformation, using ever more sophisticated technology such as artificial intelligence, now also threaten democracy itself — both by fueling extremist groups and by encouraging distrust.

“I think the post-truth world may be a lot closer than we’d like to believe,” said A.J. Nash, vice president for intelligence at ZeroFox, a cybersecurity firm that tracks disinformation. “What happens when no one believes anything anymore?”

Extremists and authoritarians deploy disinformation as potent weapons used to recruit new followers and expand their reach, using fake video and photos to fool their followers.

And even when they fail to convince people, the conspiracy theories embraced by these groups contribute to mounting distrust of authorities and democratic institutions, causing people to reject reliable sources of information while encouraging division and suspicion.

Melissa Sell, a 33-year-old Pennsylvania resident, is among those who has lost faith in the facts.

“If it’s a big news story on the TV, the majority of the time it’s to distract us from something else. Every time you turn around, there’s another news story with another agenda distracting all of us,” she said. Sell thinks the Maui wildfires may have been intentionally set, perhaps to distract the public, perhaps to test a new weapon. “Because the government has been caught in lies before, how do you know?” she said.

Absent meaningful federal regulations governing social media platforms, it’s largely left to Big Tech companies to police their own sites, leading to confusing, inconsistent rules and enforcement. Meta, the owner of Instagram and Facebook, says it makes an effort to remove extremist content. Platforms such as X, formerly known as Twitter, as well as Telegram and far-right sites like Gab, allow it to flourish.

Federal election officials and some lawmakers have suggested regulations governing AI, including rules that would require political campaigns to label AI-generated images used in its ads. But those proposals wouldn’t affect the ability of extremist groups or foreign governments to use AI to mislead Americans.

Meanwhile, U.S.-based tech platforms have rolled back their efforts to root out misinformation and hate speech, following the lead of Elon Musk, who fired most of the content moderators when he purchased X.

“There’s been a big step backward,” said Evan Hansen, the former editor of Wired.com who was Twitter’s director of curation before leaving when Musk purchased the platform. “It’s gotten to be a very difficult job for the casual observer to figure out: What do I believe here?”

Hansen said a combination of government regulations, voluntary action by tech titans and public awareness will be needed to combat the coming wave of synthetic media. He noted the Israel-Hamas war has already seen a deluge of fake and altered photos and video. Elections in the U.S. and around the world this year will create similar opportunities for digital mischief.

The disinformation spread by extremist groups and even politicians like former President Donald Trump can create the conditions for violence, by demonizing the other side, targeting democratic institutions and convincing their supporters that they’re in an existential struggle against those who don’t share their beliefs.

Trump has spread lies about elections, voting and his opponents for years. Building on his specious claims of a deep state that controls the federal government, he has echoed QAnon and other conspiracy theories and encouraged his followers to see their government as an enemy. He even suggested that now-retired Army Gen. Mark Milley, whom Trump himself nominated to be the top U.S. military officer during his administration, was a traitor and deserved execution. Milley said he has had to take security precautions to protect his family.

The list of incidents blamed on extremists motivated by conspiracy theories is growing. The Jan. 6, 2021, riot at the U.S. Capitol, attacks on vaccine clinics, anti-immigrant fervor in Spain; and anti-Muslim hate in India: All were carried out by people who believed conspiracy theories about their opponents and who decided violence was an appropriate response.

Polls and research surveys on conspiracy theories show about half of Americans believe in at least one conspiracy theory, and those views seldom lead to violence or extremism. But for some, these beliefs can lead to social isolation and radicalization, interfering with their relationships, career and finances. For an even smaller subset, they can lead to violence.

The credible data that exists on crimes motivated by conspiracy theories shows a disturbing increase. In 2019, researchers at the University of Maryland’s National Consortium for the Study of Terrorism and Responses to Terrorism identified six violent attacks in which perpetrators said their actions were prompted by a conspiracy theory. In 2020, the year of the most recent survey, there were 116.

Laws designed to rein in the power of social media and artificial intelligence to spread disinformation aren’t likely to pass before the 2024 election, and even if they are, enforcement will be a challenge, according to AI expert Vince Lynch, CEO of the tech company IV.AI.

“This is happening now, and it’s one of the reasons why our society seems so fragmented,” Lynch said. “Hopefully there may be AI regulation someday, but we are already through the looking glass. I do think it’s already too late.”

To believers, the facts don’t matter.

“You can create the universe you want,” said Danielle Citron, a professor at the University of Virginia School of Law who studies online harassment and extremism. “If the truth doesn’t matter, and there is no accountability for these false beliefs, then people will start to act on them.”

Sell, the conspiracy theorist from Pennsylvania, said she began to lose trust in the government and the media shortly after the 2012 Sandy Hook Elementary School shooting in Newtown, Connecticut, that left 20 students and six educators dead. Sell thought the shooter looked too small and weak to carry out such a bloody act, and the gut-wrenching interviews with stricken loved ones seemed too perfect, almost practiced.

“It seemed scripted,” she said. “The pieces did not fit.”

That idea — that the victims of the rampage were actors hired as part of a plot to push gun control laws — was notably spread by conspiracy theorist Alex Jones. The families of Sandy Hook victims sued, and the Infowars host was later ordered to pay nearly $1.5 billion in damages.

Claims that America’s elected leaders and media cannot be trusted feature heavily in many conspiracy theories with ties to extremism.

In 2018, a committed conspiracy theorist from Florida mailed pipe bombs to CNN, former Secretary of State Hillary Clinton and several other top Democrats; the man’s social media feed was littered with posts about child sacrifice and chemtrails — the debunked claim that airplane vapor clouds contain chemicals or biological agents being used to control the population.

In another act of violence tied to QAnon, a California man was charged with using a speargun to kill his two children in 2021. He told an FBI agent that he had been enlightened by QAnon conspiracy theories and had become convinced that his wife “possessed serpent DNA and had passed it on to his children.”

In 2022, a Colorado woman was found guilty of attempting to kidnap her son from foster care after her daughter said she began associating with QAnon supporters. Other adherents have been accused of environmental vandalism, firing paintballs at military reservists, abducting a child in France and even killing a New York City mob boss.

The coronavirus pandemic, with its attendant social isolation, created ideal conditions for new conspiracy theories as the virus spread fear and uncertainty around the globe. Vaccine clinics were attacked, doctors and nurses threatened. 5G communication towers were vandalized and burned as a wild theory spread claiming they were being used to activate microchips hidden in the vaccine. Fears about vaccines led one Wisconsin pharmacist to destroy a batch of the highly sought after immunizations, while bogus claims about supposed COVID-19 treatments and cures led to hospitalizations and death.

Few recent events, however, display the power of conspiracy theories like the Jan. 6 insurrection, when thousands of Trump supporters stormed the Capitol, vandalized the offices of Congress and fought with police in an attempt to disrupt the certification of the 2020 election.

More than 1,200 people have been charged with Capitol riot-related crimes. About 900 have pleaded guilty or been convicted after trials. Over 750 have been sentenced, with roughly two-thirds receiving some term of imprisonment, according to data compiled by The Associated Press. Many of those charged said they had bought into Trump’s conspiracy theories about a stolen election.

“We, meaning Trump supporters, were lied to,” wrote Jan. 6 defendant Robert Palmer in a letter to a judge, who later sentenced him to more than five years for attacking police. “They kept spitting out the false narrative about a stolen election and how it was ‘our duty’ to stand up to tyranny.”

Many conspiracy theorists reject any link between their beliefs and violence, saying they’re being blamed for the actions of a tiny few. Others insist these incidents never occurred, and that events like the Jan. 6 attack were actually false-flag events concocted by the government and media.

“Lies, lies lies: They’re lying to you over and over and over again,” said Steve Girard, a Pennsylvania man who has protested the incarceration of Jan. 6 defendants. He spoke to the AP while waving a large American flag on a busy street in Washington.

While they may have taken on a bigger role in our politics, surveys show that belief in conspiracy theories hasn’t changed much over the years, according to Joe Uscinski, a University of Miami professor and an expert on the history of conspiracy theories. He said he believes that while the internet plays a role in spreading conspiracy theories, most of the blame lies with the politicians who exploit believers.

“Who was the bigger spreader of COVID misinformation: some guy with four followers on Twitter or the president of the United States? The problem is our politicians,” Uscinski said. “Jan. 6 happened, and people said: ‘Oh, this is Facebook’s fault.’ No, the president of the United States told his followers to be at this place, at this time and to fight like hell.”

Governments in Russia, China, Iran and elsewhere have also pushed extremist content on social media as part of their efforts to destabilize Western democracy. Russia has amplified numerous anti-U.S. conspiracy theories, including ones claiming the U.S. runs secret germ warfare labs and created HIV as a bioweapon, as well as conspiracy theories accusing Ukraine of being a Nazi state.

China has helped spread claims that the U.S. created COVID-19 as a bioweapon.

Tom Fishman, the CEO at the nonprofit Starts With Us, said that Americans can take steps to defend the social fabric by turning off their computer and meeting the people they disagree with. He said Americans must remember what ties them together.

“We can look at the window and see foreshadowing of what could happen if we don’t: threats to a functioning democracy, threats of violence against elected leaders,” he said. “We have a civic duty to get this right.”