A Guide To The Many Conspiracy Theories Donald Trump Has Embraced

This election year may well go down as the conspiracy-theory election, thanks to Donald Trump's ceaseless efforts to inject unsubstantiated plots into the American political debate.

In an interview with the Washington Post Monday, Trump alleged, without evidence, that Hillary Clinton was involved in the death of Vince Foster, a White House aide who committed suicide in 1993, the first year of Bill Clinton's presidency. (That came on the same day Trump, the de facto Republican nominee, unloaded a double whammy on his likely Democratic opponent, Hillary Clinton. An ad posted to Instagram by Trump's campaign alleges that Clinton's husband sexually assaulted several women.)

The raising of the Foster case is just one conspiracy in a long line Trump has embraced, including so-called birtherism, the idea that President Obama wasn't born in the United States (he was); that childhood vaccines may lead to autism (they don't); that "thousands and thousands" of Muslims in America celebrated during the Sept. 11 terrorist attacks (they didn't); even that Ted Cruz's father might have been somehow involved in a plot to kill JFK (no evidence and highly unlikely).

The facts rarely line up on Trump's side in these instances, but Trump has a history of making outlandish claims that get lots of attention. As Yale professor Jason Stanley told NPR's Sarah McCammon earlier this year, Trump's embrace of innuendo and controversial statements sends a direct message to his followers.

"He's communicating, 'I'm not held to the norms that anyone else is,' " Stanley said.

Because it's going to be a long 5 1/2 months until Election Day (but hey, who's counting?), here, in chronological order, is a far-from-comprehensive list of conspiracy theories that Trump has embraced.

Birtherism

The patient zero of Trump conspiracy theories is his 2011 claim that President Obama was not born in the United States and, therefore, not eligible to be chief executive. Backers of that theory came to be known as "birthers" and, to be clear, Trump didn't start the rumors about Obama's place of birth. But he used his fame as a reality TV personality to insert the issue into the mainstream media conversation.

In a March 30, 2011, interview with Bill O'Reilly of Fox News, for example, Trump claimed there was no evidence Obama had a valid U.S. birth certificate:

"I have a birth certificate. People have birth certificates. He doesn't have a birth certificate. He may have one but there is something on that birth certificate — maybe religion, maybe it says he's a Muslim, I don't know. Maybe he doesn't want that. Or, he may not have one."

That claim turned into weeks of cable news chatter even as fact checkers conclusively determined it lacked any substance. The issue died down only after the White House produced the long-form birth certificate Trump and other birthers claimed did not exist. (Some in that camp still question the validity because the governor of the state when it was released, Neil Abercrombie, was a friend of Obama's parents.)

Childhood vaccines and autism

Trump has repeatedly embraced the discredited theory that childhood vaccinations can lead to autism. In the second GOP presidential primary debate, hosted by CNN in September 2015, Trump didn't back down on the claim even when confronted with evidence that vaccines are safe:

"Just the other day, 2 years old, 2 1/2 years old, a child, a beautiful child went to have the vaccine, and came back, and a week later got a tremendous fever, got very, very sick, now is autistic."

A 2013 study by the Centers for Disease Control and Prevention found no connection between childhood vaccines and a risk of autism.

The Sept. 11 attacks — "Thousands and thousands" of Muslims cheering in the streets

Campaigning in Alabama last November, Trump claimed that Muslims in New Jersey celebrated the attacks on the World Trade Center on Sept. 11, 2001:

"Hey, I watched when the World Trade Center came tumbling down. And I watched in Jersey City, N.J., where thousands and thousands of people were cheering as that building was coming down. Thousands of people were cheering. So something's going on. We've got to find out what it is."

Trump repeated the claim multiple times over the following days, repeating an Internet rumor that has circulated since the attacks despite comprehensive reporting from that time that debunked the claims.

FactCheck.org ran down Trump's various claims and concluded:

"What's clear to us — and should be to Trump — is that there were no widespread televised celebrations in New Jersey on 9/11. In fact, what Trump described would have been big news, and the reporters at the Daily News, Star-Ledger and elsewhere who tried and failed to track down rumors of 9/11 celebrations could have just turned on the TV to get their story."

Antonin Scalia's death: "They say they found a pillow on his face"

Just days after the death of Supreme Court Justice Antonin Scalia at a ranch in Texas this past February, Trump weighed in on claims that Scalia had been murdered. In an interview with radio host Michael Savage, Trump said, "They say they found a pillow on his face, which is a pretty unusual place to find a pillow," before saying he was unable to respond further.

The Presidio County District Attorney cited a letter from Scalia's doctor that said the 79-year-old justice suffered from a variety of ailments that very likely contributed to his death and there was nothing suspicious about his body when it was discovered on Feb. 13, 2016, according to the Associated Press.

Trump also suggested, without evidence, that President Obama did not attend Scalia's funeral because Obama might be a secret Muslim. Scalia was Catholic.

Ted Cruz's father might have had a role in the JFK assassination

On the cusp of wrapping up the Republican nominating contest earlier this month, Trump went to the well of one of the most enduring conspiracy theories in American life: the assassination of President John F. Kennedy in 1963.

Citing an as-yet unsubstantiated story in the National Enquirer, Trump said in an interview on Fox News that that his GOP rival Ted Cruz's father, Rafael Cruz, was spotted with JFK assassin Lee Harvey Oswald:

"What was he doing with Lee Harvey Oswald shortly before the death, before the shooting? It's horrible."

The supermarket tabloid's claim rests on a grainy, 53-year-old photo that purports to show Cruz alongside Oswald. Facial recognition experts consulted by PolitiFact said there was no evidence Cruz was in the photo and that it was highly unlikely a young Rafael Cruz would have run in Oswald's circles. The fact-checking group rated Trump's claim "Pants on Fire" false.

Vince Foster's death

This week, Trump also embraced the ur-Clinton conspiracy theory: the 1993 death of White House aide Vince Foster. Foster was an Arkansas ally of the Clintons' who served as deputy White House counsel at the start of the first Clinton term. He was found dead in his car in Virginia in July 1993.

Foster's death sparked years of conspiracy-theorizing from Clinton's opponents about whether the facts behind his death were covered up to hide financial misbehavior. Foster's death was cited in investigations into the Clintons' real estate investments with the Whitewater Development Corp. (yes, that Whitewater). Multiple investigations by various federal agencies and independent counsels throughout the rest of the 1990s concluded that Foster's death was a suicide and that was he was clinically depressed when he died.

But in an interview published by the Washington Post on Monday, Trump dismissed those investigations and claimed that the circumstances of Foster's death were "very fishy":

" 'He had intimate knowledge of what was going on,' Trump said, speaking of Foster's relationship with the Clintons at the time. 'He knew everything that was going on, and then all of a sudden he committed suicide.'

"He added, 'I don't bring [Foster's death] up because I don't know enough to really discuss it. I will say there are people who continue to bring it up because they think it was absolutely a murder. I don't do that because I don't think it's fair.' "

Context on Bill Clinton and claims of sexual assault

Trump's latest attack ad claims former President Bill Clinton sexually assaulted several women while president during the 1990s. It uses archival tape of former White House intern Monica Lewinsky; Kathleen Willey, a former White House volunteer, who says Clinton groped her in 1993; and Juanita Broaddrick, who says Clinton raped her in 1978.

Clinton did have a sexual relationship with Lewinsky that resulted in an unsuccessful impeachment trial in the U.S. Congress. Lewinsky has never claimed Clinton assaulted her. Clinton denied Willey's and Broaddrick's allegations.

As reported by the Washington Post, an independent prosecutor investigating Clinton at the time found there was "insufficient evidence" to charge Clinton with lying about Willey. Clinton also denied the allegations about Broaddrick, and no charges were ever filed against him.

The Post also concludes that Trump's attacks against Clinton on these allegations are hypocritical given that Trump was quoted on the record at the time as being extremely dismissive of the various claims against Clinton. (For future reference, the Post's Glenn Kessler has also done yeoman's work putting together a short guide to all of the sexual allegations leveled against Bill Clinton.)

Bonus: Is Trump's candidacy a Democratic conspiracy?

Perhaps the best Trump conspiracy theory is the one he doesn't embrace: that Trump's candidacy is the product of a conspiracy.

Shortly after he entered the Republican nomination race last summer, blogger Justin Raimondo said that Trump was trying to help, get ready for it ... Hillary Clinton:

"Donald Trump is a false-flag candidate. It's all an act, one that benefits his good friend Hillary Clinton and the Democratic party that, until recently, counted the reality show star among its adherents. Indeed, Trump's pronouncements — the open racism, the demagogic appeals, the faux-populist rhetoric — sound like something out of a Democratic political consultant's imagination, a caricature of conservatism as performed by a master actor."

After all, Trump was once a registered Democrat — and had backed policies such as increased taxes on the wealthy, gun control and single-payer health care. He praised the Clintons for many years, donated money to them and even invited them to his third wedding.

As Trump himself might say, I don't know if it's true, but it seems fishy.

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