Disinformation enabled Donald Trump’s second term and is a crisis for democracies everywhere

Donald Trump did not win the 2020 election, but asserting that he did became a prerequisite for Republicans standing for nomination to Congress or the Senate to win their primaries. An entire party became a vehicle for disinformation.1 Trump did win the 2024 presidential election, and key to that victory was building on the success of that lie. If you control enough of the information ecosystem, truth no longer matters.

Another telling example: Haitian migrants in Springfield, Ohio, are not eating cats and dogs. US vice president elect, JD Vance, the source of that claim, admitted as much even as he justified it. “If I have to create stories so that the American media actually pays attention to the suffering of the American people, then that’s what I'm going to do,” he said.2

Disinformation in politics is nothing new. History is replete with claims that were fabricated to advance political aims. Although threats were made against the local authorities in Springfield, no lives were lost. But in other cases, they were. US president Lyndon B Johnson used a fictitious attack on US ships to justify US involvement in Vietnam. British involvement in the Iraq invasion in 2003 was justified by a “dodgy dossier.” Readers of The BMJ will recall the huge amounts of misinformation (wrong or misleading content that is unknowingly shared) and disinformation (false content that is deliberately spread) during the covid-19 pandemic, some generated or amplified by politicians.3 This reduced vaccine uptake,4 promoted ineffective treatments, and encouraged attacks on health workers.5 In the past, factually incorrect statements might have had only local consequences, but a lie can now circle the world in seconds.6 Yet the speed in which disinformation can spread is only part of the problem.

Modern online information is vulnerable to the human desire to seek content that provokes anger.78 Social media platforms, which profit from increased engagement, are designed to reward such content,9 and organised networks exploit this to spread disinformation.10 The 2024 US presidential campaign saw conspiracy theories and disinformation deliberately exploited by the Trump campaign and its supporters in a frighteningly powerful ecosystem created by a charismatic populist and media billionaires.11

Twitter (now X) already struggled with moderating disinformation, conspiracy theories, and extremist content before Elon Musk’s takeover in 2022. But at least in the past, it tried. Among Musk’s first actions on buying the company was a drastic reduction in online moderation, accompanied by a relaxation of previous safeguarding rules.12131415 Coupled with the sale of verification ticks and adjustment of algorithms, these actions greatly facilitated the spread of disinformation and extreme right wing views.161718 This was by design: part of Musk’s reason for buying Twitter was to influence the social discourse.19 And influence he did—by using his enormous platform (203 million followers) to endorse Trump, spread disinformation about voter fraud2021 and deep fakes of Kamala Harris,2223 and amplify conspiracy theories about everything from vaccines to race replacement theory to misogyny.2425 Musk’s platform is effective: his endorsement of Trump coincided with Republican leaning posts being algorithmically favoured over Democrat leaning posts.26 A more mundane example: after Musk published three non-evidence based posts on X that favoured one medication over another, sales of the former rose by 18% while the other fell by 11%.27

It’s tempting to say that X is just one platform, that it couldn’t happen in the UK, and that this is restricted to the US. But this is wishful thinking—remember the spread of disinformation about the 2024 UK riots, which was aided directly by Musk.28 The 2024 presidential election provides a powerful playbook for populist extremists everywhere.

The playbook involves destabilising the online information system to radicalise people and build distrust of public figures, scientists, and the mainstream media. These methods have already been shown to work. The more time people spend engaging with conspiracy theories and disinformation online, the more they’ll seek out such content, and radicalisation can happen remarkably quickly.29 The world had a front row seat to Elon Musk’s own self-radicalisation on X.30

The playbook involves putting conspiracy theorists at the heart of government and dismantling agencies that support evidence based policy making. Trump has promised Robert F Kennedy a “big role in the administration.”31 Kennedy is a well known critic of vaccines, continuing to promote the discredited idea that they can cause autism.3233 He has been especially critical of covid-19 vaccines and experts who promote their use, writing a book attacking Anthony Fauci.34 He has also argued that SARS-CoV-2 is “ethnically targeted”35 and is opposed to water fluoridation. Meanwhile, the Centers for Disease Control and the Food and Drug Administration are in Kennedy’s sights, with Trump indicating that he will offer him free rein.36

Democracies rely on voters to make informed choices in a free and fair way. But when a substantial proportion of the population, especially younger or less educated voters, get their information from unaccountable, unregulated, social media platforms such as TikTok, Facebook, or X, how free and fair is the process?

The warning signs are clear for democracies around the world. Firstly, governments must regulate social media companies more rigorously. Brazil’s victorious dispute with X shows what is possible,37 and a major battle between the European Commission and Musk is under way.38 Beyond that, we must grapple with how to hold the world’s richest people to account when they directly interfere with national and international politics.

Secondly, public health agencies must create robust surveillance systems for infodemics just as they have for epidemics. They must monitor the emergence of disinformation and counter it or, ideally, anticipate and counter (pre-bunk) it among vulnerable audiences (and build population resilience).39 Independent organisations that are countering disinformation are already being deliberately targeted (https://counterhate.com/). And we must accelerate research on “inoculating” people against the algorithms and content that attempt to radicalise them.

Finally, politicians and the public health community must not be afraid of calling out disinformation, and we must all support and applaud them in doing so. And moving beyond responding to false rhetoric, we must also get on the front foot and create compelling counter narratives of a better politics that can support a kinder, more inclusive, and socially just world.