Why JFK conspiracy theories live on 50 years later

"Who actually fired the shots that killed Kennedy? Why did Ruby shoot Oswald? Was there a conspiracy?" (Via U.S. National Archives)

The official story, of course, is Lee Harvey Oswald acted alone when he shot at the president's motorcade from the sixth-floor window of the Texas School Book Depository. (Via Wikimedia Commons)

But whether it's the CIA, the Mafia, the Soviets, the Cubans or even UFOs, conspiracy theories surrounding JFK's death live on in books and film. (Via Discovery)

"We've come to know it as the magic bullet theory."

But the conspiracy holders aren't alone . ​(Via Warner Bros. / "JFK")

But the conspiracy holders aren't alone.

The birthers will tell you President Obama isn't really a U.S. citizen. (Via ABC)

And the 9/11 truthers say George W. Bush was really behind 9/11. (Via CBS)

Absurd as these ideas might seem, they're quite common. Polls show at least half of all Americans believe in at least one conspiracy theory, even when there's no credible or convincing evidence.

Why? The Christian Science Monitor's Patrik Jonsson suggests it's in our very nature as Americans, writing: "In a country where the Founding Fathers' distrust of government is enshrined in the Constitution, conspiracy theories often give wider scope to that worldview."

Still, you'd think in the age of the Internet, some of the more out-there theories would be laid to rest.

But confirmation bias — the idea that we seek out confirmation, not information — is a very real thing. And Google hasn't helped.

As The New York Times' Maggie Koerth-Baker puts it: "It can be comforting to do your own research even if that research is flawed. It feels good to be the wise old goat in a flock of sheep."

But of all the conspiracy theories, doubts surrounding Kennedy's death resonate the most. A recent poll found 59 percent of Americans believe there's more to the story — the U.S. secretary of state included.

JOHN KERRY: "I have serious doubts that Lee Harvey Oswald acted alone." (Via NBC)

So what makes JFK so different? Writing in The Washington Post, two University of Miami political scientists theorize: "The victim was an American president and the potential villains include actors of immense reach and influence. … Anyone, regardless of political affiliation, can find a detested powerful actor to blame."

In other words, the idea that the American president could be taken down by a lone shooter may be too hard to swallow. The conspiracy theories, however crazy they may be, in a way give us comfort. (Via John F. Kennedy Presidential Library and Museum)

But perhaps it was Kennedy himself who said it best: "For the great enemy of truth is very often not the lie — deliberate, contrived and dishonest — but the myth — persistent, persuasive, and unrealistic." (Via John F. Kennedy Presidential Library)

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