Neutral information about Jews triggers conspiracy thinking in Trump voters, study finds
A study published in Political Research Quarterly has uncovered a notable link between antisemitism and conspiracy theories, with significant differences based on political affiliation. For supporters of Joe Biden, exposure to conspiracy content heightened their views of Jewish political and economic power, while for supporters of Donald Trump, even impartial information about Jewish history led to increased belief in conspiracy theories.
“I have been concerned by rising levels of antisemitism in mainstream political discourse over the past decade. In particular, it seemed to be the case that the rising tides of conspiracy beliefs and right-wing populism were ushering in a growing tolerance for antisemitic statements, actions, and beliefs,” explained study author Jacob S. Lewis (@profjslewis), an assistant professor at Washington State University.
It has been observed that conspiracy theories, antisemitism, and populism often appear together, but the reasons behind these connections and the direction of any causal relationships remained unclear. For example, it was unknown whether the current surge in antisemitism is a consequence of populism, or if these are all separate symptoms of a deeper, unexamined societal issue. This lack of clarity is especially troubling given the real-world dangers of antisemitic conspiracy theories.
In his new study, Lewis aimed to experimentally investigate the causal links between these phenomena and how they operate across different political groups. Understanding these relationships is important for addressing the growing problem of political antisemitism and its intersection with conspiracy beliefs in contemporary society.
Lewis conducted two online survey experiments in both the United States and the United Kingdom. Participants in the United States were recruited through an online platform called Prolific and were specifically chosen to represent both supporters of Joe Biden and Donald Trump from the 2020 presidential election. Approximately 1,000 individuals who reported voting for Joe Biden and 1,000 who voted for Donald Trump were included in the study from the U.S.
In the United Kingdom, a similar approach was used, targeting voters who supported either left-leaning or right-leaning political parties. Around 800 supporters of left-wing parties and 800 supporters of right-wing parties were recruited. This method of sampling ensured representation from different parts of the political spectrum in both countries.
The surveys used what is known as a “stacked treatment design.” This means that participants were randomly assigned to receive different pieces of information, called “vignettes,” at different points in the survey.
There were three main types of vignettes, each with a corresponding control condition where participants received neutral information instead. The first type of vignette was about populism, focusing on how politicians can accumulate wealth despite economic inequality. In the U.S. version, this vignette discussed efforts to regulate stock trading by politicians, mentioning both Democratic and Republican involvement. The UK version highlighted politicians gaining lucrative positions in private companies.
The second type of vignette was about conspiracy theories, specifically focusing on the World Economic Forum and its “Great Reset” plan, a topic frequently associated with various conspiracy narratives online. This vignette included images of social media posts spreading these conspiracy theories.
The third type of vignette was designed to make Jewish identity noticeable without being negative or conspiratorial. This vignette presented factual information about Jewish immigration to the United States and the contributions of Jewish people to the development of Hollywood and Broadway, accompanied by pictures of well-known Jewish actors.
Participants were randomly assigned to either receive one of these vignettes or a neutral control vignette at each of the three stages of the survey. The control vignettes contained general, non-political information, such as infrastructure improvement efforts in the U.S., economic inequality in the UK, climate change and wildfires, and airline flight cancellations. This design resulted in eight different groups of participants, each receiving a unique combination of vignettes or control information, allowing for the examination of how exposure to populism, conspiracy theories, and information about Jewish people might interact.
To measure the impact of these vignettes, Lewis used several sets of questions. To assess antisemitic attitudes, participants were asked to rate the political and economic influence of various groups, including Jewish people, on a scale from “none at all” to “too much.” The phrase “too much” was intentionally used to tap into the idea that certain groups might have undue or unwarranted power.
Participants were also asked to indicate their agreement with a series of statements about free speech, including some statements that echoed antisemitic tropes about Jewish control and censorship. Additionally, to further gauge antisemitic beliefs, participants were presented with classic antisemitic statements from the Anti-Defamation League, such as whether Jews are more loyal to Israel than to their country of residence.
Populist attitudes were measured using statements reflecting a black-and-white view of politics, such as “Politics is a battle between good and evil,” and beliefs that the system is rigged against ordinary people. Finally, to measure belief in conspiracy theories, participants were asked to rate how likely they thought various conspiracy theories were to be true. These theories included those about COVID-19 being intentionally created “to control normal Americans” and the 9/11 attacks being a false flag operation.
The study’s results revealed distinct patterns in the United States, particularly among supporters of different political candidates.
“It is worth noting that this is exploratory research about antisemitism, conspiracy beliefs, and populism,” Lewis told PsyPost. “The core question revolves around, essentially, what causes what? There’s good reason to believe they are interlinked, but it is difficult to know whether they are causally related. I use a novel approach to survey experiments and find that, in the American context, the causal pathways between antisemitism and conspiracy belief are different on the political left and the political right.”
Among individuals who voted for Joe Biden in 2020, exposure to the conspiracy theory vignette led to a statistically significant increase in their perception of Jewish people’s political and economic power. This suggests that for this group, being primed with conspiracy-related information made them more likely to attribute excessive power to Jewish people.
For Trump supporters, the findings were somewhat unexpected. Even though the vignette about Jewish people provided neutral and positive information about their contributions to culture, it led these respondents to show an increased belief in conspiracy theories. In other words, when Trump voters were simply reminded of Jewish identity, they became more inclined to think that events such as the COVID-19 outbreak were deliberately planned to control the public and that the war in Ukraine was orchestrated as part of a Zionist plot. This result implies that, for this group, drawing attention to Jewish heritage—even in a nonnegative way—can serve as a trigger that amplifies preexisting conspiratorial ideas.
Further statistical analyses, which looked at the combined effects of different types of information, supported this pattern. They revealed that exposure to the conspiracy-themed vignette tended to raise perceptions of Jewish power among participants regardless of their political leanings. However, when the “Jewish” vignette was combined with either populism or conspiracy messages, the boost in conspiracy beliefs was particularly pronounced among Trump supporters.
“When supporters of Donald Trump (in the 2020 election) are exposed to brief vignettes about Jewish Americans, they become substantially more likely to endorse certain conspiracy theories,” Lewis said. “And when supporters of Joe Biden (in the 2020 election) are exposed to a brief vignette about the ‘Great Reset’ World Economic Forum conspiracy theory, they increase their evaluations of Jewish economic and political power.”
Notably, the study conducted in the United Kingdom did not find similar effects. Participants in the UK, regardless of their political leaning, did not show significant changes in their attitudes or beliefs in response to the vignettes. Furthermore, UK participants generally expressed lower levels of belief in conspiracy theories compared to their American counterparts, particularly when compared to right-leaning Americans.
While UK participants showed lower overall endorsement of conspiracy theories, there was an interesting divergence regarding a classic antisemitic trope: left-leaning voters in the UK were more likely than left-leaning voters in the US to agree with the statement that “Jews are more loyal to Israel than to [their country].”
It is also important to note that the vignette designed to evoke populist sentiments did not have a noticeable effect on participants’ responses, which was unexpected given existing research linking populism and conspiracy beliefs. Future studies might explore different ways of priming populist attitudes.
“I wanted to also measure the relationship of antisemitism and conspiracy belief to populism. I found that my populist vignettes and questions were not at all effective,” Lewis noted. “This might be because I had a bad theoretical assumption (about there being a linkage), or it might be something to do with my research design. I’m not sure right now!”
The study also focused on voters from the 2020 election, and further research could examine how these relationships evolve with changing political alignments. “As with all research, this study is limited by when it was done,” Lewis said. “We have seen an incredible political upheaval over the past ten years, and political affiliations with the ‘right’ or ‘left’ have been changing rapidly. This research occurred over the course of a year during the Biden administration.”
“Would the results differ now, following the re-election of Trump? Moreover, there are questions about selection (who decides to take a survey), measurement, and more. I see this study as a foundation for future research, not a final answer. It is also worth noting that this research builds in existing work by Royden and Hersh that was published in Political Research Quarterly.”
“My hope is that this research will contribute to building a sincere interest within the field of political science to study antisemitism in the same way that we study other forms of bias and hatred,” Lewis added.
The study, “Conspiracy and Antisemitism in Contemporary Political Attitudes,” was published February 1, 2025.
