Joseph Uscinski is Associate Professor of Political Science at University of Miami. He is co-author of American Conspiracy Theories (Oxford University Press, 2014).

This weekend, former New York Mayor Rudy Giuliani told Fox News Sunday viewers that Hillary Clinton was seriously ill. The media, he said, “fails to point out several signs of illness by her. … Go online. Search for ‘Hillary Clinton illness.’ Take a look at those videos for yourself.”

The idea that Clinton is secretly wrestling with some unknown illness is just the latest conspiracy theory to go mainstream in an election season chock full of them. Conspiracy theories, which I’ve studied for the past seven years, have always been part of American politics, but they’ve tended to pop up in the dark corners of our political discourse, serving mainly as sideshows to more important political disputes. Not so this year; I’ve never seen a time when they so dominated the mainstream debate—and when they had the potential to do so much harm.


Whether it was witches colluding with Satan during colonial times, Freemasons nefariously controlling the government in the 1800s or communists coopting the State Department during the Red Scare, Americans have always been drawn to the idea that certain people or organizations are working in secret for their own benefit against the public good. Polls suggest that all Americans believe in at least one conspiracy theory; most believe in several. At the height of birtherism a few years ago, about a quarter of Americans believed that President Barack Obama was born outside the United States. A similar number believed there was a conspiracy behind the terror attacks of 9/11. More than 50 years after the fact, a majority of Americans continue to believe that President John F. Kennedy’s assassination was due to a conspiracy rather than to a lone gunman. In 2012, when I asked a representative sample of Americans to agree or disagree with the following statement, “Big events like wars, the current recession, and the outcomes of elections are controlled by small groups of people who are working in secret against the rest of us,” only 30 percent disagreed.

Despite this, the United States has not gone off the conspiracy theory cliff because our elite politicians and mainstream news sources generally eschew this type of heady theorizing. A few politicians or news sources might allege a plot from time to time (think Sarah Palin and her Obamacare death panels), but these are usually a result of overheated partisan rhetoric and they tend to receive intense backlash.

That was, until now. Donald Trump, one of two people likely to be president next year, has been propagating, and now creating, conspiracy theories as a major theme of his campaign.

There’s an obvious reason for this: Donald Trump has branded himself an “outsider.” In my research, I have found that conspiracy theories tend to work best when they are employed by outsiders, electoral losers and statistical minorities. These “losers” have to use conspiracy theories to justify their outsider status, explain away losses and call accepted practices into question. If you want to explain why you want to tear the accepted system down in favor of a new approach or if you want to enter the White House without ever being part of the political establishment, then it is fitting to use conspiracy theories to call that system into question.

As for Clinton, the environment created by two outsiders—Sanders and Trump—has forced her to respond in kind. She is under pressure to give lip service to Sanders’ economic conspiracy theories in order to attract his supporters. And she has also been forced her to push back on Trump’s conspiracy theories about her with conspiracy charges of her own.

There is nothing fundamentally wrong with conspiracy theories. They have their positive attributes: Sometimes they turn out to be true (think Watergate, for example), and sometimes they bring new information to light (such as securing the release of many documents pertaining to the Kennedy assassination). But too many can distort our perception of reality, squander precious government time and resources and endanger lives—especially when they move out of the fringes of political life and become the currency of the truly powerful.

Here are the five most dangerous conspiracy theories of 2016 (and some honorable mentions).

1. Mexicans and refugees are murderers, rapists and terrorists

Danger: Violence

Donald Trump has accused Mexican immigrants of being pawns in a Mexican conspiracy to send murderers and rapists to America. He also has accused refugees, fleeing their tattered homeland and shattered lives, of working against the government as ISIL agents.

Most conspiracy theories in the United States resonate when they are levied by the weak and accuse the strong (when out-of-power Democrats accused the Bush administration of being behind 9/11, for example). These conspiracy theories are usually annoying at worst, because those accused of conspiring are well-protected and powerful. In this case, however, the typical model is reversed: The strong (a man running for U.S. president with the backing of a major political party) is accusing the weak (refugees and minorities). This is a more dangerous type of conspiracy theory because those in power can actually act on their wild hunches, sometimes with deadly consequences. If a President Trump were to act on his conspiracy theories, for example, it could spell doom for those groups in the United States. And those who believe Trump’s rhetoric might choose to act on their own by doing violence to the targets of Trump’s theories.

Just look at what has happened when similar conspiracy theories have caught on before: There are the Salem Witch Trials, where innocent women were brutally murdered; the Red Scare of the 1950s, which saw the United States government violating the rights of countless Americans; and the Japanese internment camps during WWII. When the powerful believe there is a conspiracy against them—real or not—their reactions can have terrible consequences.



2. “There’s something going on”

Danger: Mass paranoia

A favorite go-to conspiracy theory of Trump’s, used in different circumstances at different points during the campaign, these four words suggest that our governmental institutions and our institutions for disseminating information are not only malevolent, but also engaged in a cover-up of epic proportions.

This conspiracy theory is useful for Trump because it lets him avoid specifics; it’s also dangerous because it’s open-ended, leaving Trump supporters plenty of room to connect their own dots. What is, in fact, “going on”? It could be Radical Islamic Terrorists in your neighborhood, refugees armed with ISIL cellphones or a president who either doesn’t care about terrorist attacks on the homeland or is directly involved in them. Maybe a terrorist lives next door, maybe the FBI is actually aiding the terrorists. Maybe our president is a terrorist, too. Who knows, right? But these four words suggest that everyone is in on it, we need to watch our neighbors, keep an eye on the government and watch the president’s body language like a hawk.

This style of conspiracy theorizing—leaving the details for people to figure out on their own—is advantageous because it gives people less to disagree with. What I have found in my research is that the more details there are to a conspiracy theory, the more reasons there are for people to take issue with it. This is one reason why JFK assassination conspiracy theories continue to be so popular compared to others. There is no established villain or plot line; everyone gets to choose the version that makes most sense to him or her.





View Conspiracy theories of 2016 The biggest conspiracy theories of 2016.

3. Trump/Clinton is a Manchurian Candidate

Danger: Institutional distrust, political polarization

Criticizing Clinton for her mishandling of classified emails, Trump suggested that the Democratic nominee is now beholden to the Obama administration, which decided not to prosecute her. Trump also suggested that other countries now have evidence to blackmail or control Clinton, given that they have been able to hack her private email server. Shooting back, the Clinton campaign put out an ad suggesting that Trump is an agent of powerful Russian interests.

Americans of all political persuasions should be able to trust that the two candidates who could lead the national government aren’t pawns to other interests. When they start to doubt their leaders’ loyalty to the country, institutional distrust can skyrocket. It’s also not that easy for a president to shed a conspiracy theory about him or her: The birther theory that dogged Obama during his entire time in the White House has been a distraction for both his administration and the country—and birtherism started with far less fanfare than these current accusations.

These sorts of theories can also be symptoms of, or possibly even contribute to, political polarization. By always calling into question a president’s motives, people on the opposing side never have to engage in meaningful debates over policy.

4. Vast right-wing conspiracy

Danger: Lack of accountability

There are conspiracy theories; and then there are conspiracy theories about conspiracy theories. This particular one was born during the height of the investigations into then-President Bill Clinton’s business practices and personal life. During a Today Show interview, then-first lady Hillary Clinton dismissed the burgeoning Monica Lewinsky scandal: “The great story here for anybody willing to find it and write about it and explain it,” she said, “is this vast right-wing conspiracy that has been conspiring against my husband since the day he announced for president.”

Conspiracy theories aren’t reserved for Republicans. Hillary Clinton has held on to her conspiracy theory that the right wing is in league against her and her family to this day; in fact, she claimed this election cycle that the conspiracy is “even better-funded” now.

Here’s the problem: If followed to its conclusion, this conspiracy theory suggests that every criticism, every accusation and every investigation of the Clintons is nothing but a well-orchestrated and false attack by an enormous network of clandestine operatives—giving Clinton and her supporters any easy way to dismiss any charges leveled against her. The Clintons are likely not guilty of all they have been accused. But they have made mistakes and they should be accountable for those. Appealing to a conspiracy should not alleviate a president or presidential candidate from responsibility.



5. Everything is “rigged”

Danger: Disenfranchisement and alienation

The campaigns of Trump and Sanders repeatedly alleged during the primaries that the nomination process is rigged. Earlier this month, Trump claimed that in states without voter ID laws in place, fraud will be rampant and people will be voting “15 times.” And he asserted that the only way the Clinton campaign can win Pennsylvania is if “they cheat.”

We’ve seen what can happen when people seize on conspiracy theories about fraudulent and rigged elections—despite there being no evidence of mass voter fraud. Over the past few years, similar beliefs have led state legislatures across the country to enact restrictive voter ID laws. But rather than fix a system that wasn’t broken to begin with, these efforts have been shown to disenfranchise minority voters. This year, if Trump deploys supporters to polling stations across America to monitor for fraud and challenge voters’ legitimacy as he is promising to do, the results could be similar.

But such claims about election fraud pale in comparison to the larger allegations that the entire system is rigged. Sanders and fellow Sen. Elizabeth Warren frequently claimed during this election cycle that the economic and political systems are entirely rigged. Here’s the problem with that theory: The United States has a $20 trillion economy and a political system that is widely diffused across different branches and levels. Being familiar with the failure rates of conspiracies, I can say that there is no group—not hedge-fund managers, not big bankers, not politicians—who could possibly rig our political and economic systems on any large scale and get away with it for long.

Far from being helpful, this sort of rhetoric is dangerous. First, it allows for scapegoating (“my lot in life is the fault of the 1 percent”) and indictment (“the rich and powerful have gotten that way only through illicit means”). It also brings about hopelessness and alienation—the feeling that we have been locked into an unfair and degrading system by a few people who wish to abuse us. These sorts of conspiracy theories also serve to depress the vote, as those who believe that elections and governmental processes are rigged will most likely stay home; this weakens our democracy.



HONORABLE MENTIONS

Pharmaceutical companies are hiding the connection between vaccines and autism

Danger: Death

This conspiracy theory claims that vaccines cause a series of illnesses, and that these adverse effects have been covered up by pharmaceutical companies to maintain profits. In fact, vaccines have saved millions of lives. Using the bully pulpit as both Trump and Green Party candidate Jill Stein have done to spread this conspiracy theory and undermine vaccine science will cost lives. Some people will listen to these candidates and skip vaccines for themselves and their children. We already have seen the consequences.



Big agricultural companies are hiding the negative effects of genetically modified foods

Danger: Higher food costs, damage to the environment

Sanders and Stein have both engendered GMO conspiracy theories, which claim that big agriculture and biotech companies are hiding the negative environmental and health consequences of farming and consuming genetically modified foods. This is despite the overwhelming scientific consensus that genetically modified food is safe to eat, similar to the alternatives, better for the environment and cheaper.

The dangers of these conspiracy beliefs are currently playing out in Vermont, where new legislation requires burdensome labeling of foods made from genetically modified crops (a $1,000 fine is levied per day per unlabeled product). Food choice is going down, and food prices are going up. Increased food costs can be absorbed by upper-class budgets; but they have a disproportionate impact on the budgets of people with midand lower incomes.



Ted Cruz’s father took part in the assassination of President Kennedy

Danger: A trip down the rabbit hole

It would be difficult to create any list of conspiracy theories and leave this one out, just by virtue of its creativity. Looking to deal a death blow to Ted Cruz’s campaign, Trump suggested that Cruz’s father was in a picture taken in 1963 with Lee Harvey Oswald, and therefore had a role in the assassination of JFK. Trump further claimed that the media was covering up the story.

The danger here is a bit esoteric: If people were to take Trump at his word that a sitting senator and presidential candidate’s father was involved in Kennedy’s assassination and that the media all knew about it but were purposely hiding it from the public, then nothing in this world could be taken at face value. What else would the media be hiding from us and what other horrific crimes are linked to our government officials? There would be no end to the conspiracy theorizing.

Maybe the advent of the upcoming debates will give Trump and Clinton an incentive to leave the conspiracy rhetoric behind and focus on issue-oriented politics. The likelihood, however, is that they will continue to push the country toward a conspiracy theory fueled delirium (some polls suggest an uptick in conspiracy beliefs as of late). And if they do, the results could be dire.