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17 Greatest Conspiracy Theories in American History

Current events, international affairs, government, and American history are a few of Kelley's prime interests.

Oklahoma City Bombing

Oklahoma City Bombing

During the short history of the United States, there have been plots to commit crimes, to further a cause, or to gain an advantage. In perhaps the most notable one, John Wilkes Booth and others conspired to assassinate President Abraham Lincoln and members of his cabinet in 1865. Then in 1995, Timothy McVeigh, Terry Nichols, and Michael Fortier plotted to bomb the Alfred P. Murrah Federal Building in Oklahoma City, Oklahoma.

Both of these plots led to devastating consequences for the U.S. Occasionally, conspiracies are not only theoretical; they can actually happen!


1. Conspiracy to Assassinate JFK

Perhaps the most investigated conspiracy theory in the U.S. involves the assassination of President John F. Kennedy. The Warren Commission claimed Lee Harvey Oswald was the lone assassin, although many claim Oswald was either “framed” for the murder or conspired with others.

Jack Ruby was a prime suspect in this regard because he murdered Oswald two days after the assassination. Why did Ruby kill Oswald? Was it to keep him from telling the authorities about the conspiracy? Unfortunately, Ruby took this secret to his grave when he died of cancer in January 1967.

Numerous names (including Ruby's) as well as organizations and even entire countries have been implicated in the assassination. Those implicated include: the Italian Mafia, Lyndon B. Johnson, J. Edgar Hoover, Clint Murchison, Fidel Castro, the Federal Bureau of Investigation (FBI), the Central Intelligence Agency (CIA), E. Howard Hunt, and the Soviet Union.

But no solid evidence exists for the complicity of any of the aforementioned. Pop culture begs to differ, however. Oliver Stone’s movie JFK theorizes that the assassination involved nothing less than a coup d’état orchestrated by the federal government of the U.S. Perhaps the best investigative journalism on the assassination and its conspiracy theories is the nine-part TV series The Men Who Killed Kennedy, which implicated a hired French gunman by the name of Lucien Sarti, who allegedly fired the fatal shot from the infamous grassy knoll.


2. "Manchurian Candidate" Assassinations

Many conspiracy theories involve something known as Manchurian Candidate assassins. These unwitting government “sleeper agents" may have murdered prominent people such as Robert F. Kennedy, Martin Luther King Jr., Malcolm X, and John Lennon. They most likely carried out their order at some designated point initiated by the conspirators, after undergoing a period of brainwashing, perhaps in a foreign country.

Theorists argue that government agencies such as the CIA — generally considered a conspiracy itself and often implicated in conspiracy theories — would have more powerful motives than average citizens, and would also be able to create biased commissions to investigate such crimes. Could the CIA have murdered any of these men? You're welcome to do the research.

According to the book and movie titled The Manchurian Candidate, these sleeper agents, once they have committed the assassination, would immediately forget what they had done, or perhaps, commit suicide or immediately be murdered by another government agent, destroying the link to the conspirators.

Waco Siege

Waco Siege

3. Murder of the So-Called "Waco Wackos"

The stand-off at Waco, Texas in April 1993 ended abruptly when self-proclaimed biblical prophet David Koresh, as well as 54 of his Branch Davidian followers and 21 children, were incinerated in a fire that erupted during a military assault initiated by the Bureau of Alcohol, Tobacco, and Firearms (ATF) and the FBI. The Danforth Report, released in July 2000, claimed that the fire was started by the Branch Davidians, but conspiracy theorists assert that the ATF and FBI deliberately started the fire by using incendiary devices during the siege.

These theorists also claim that the Branch Davidians never presented much of a threat, even though they were heavily armed, which isn’t a crime in the U.S. It was also alleged that the Branch Davidians were cooking up methamphetamine, which was never proven.

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Did the ATF and FBI conspire to keep the finger of blame firmly pointed at the so-called "Waco Wackos?" Ill-conceived, gung-ho sieges such as the one at Waco and at places like Ruby Ridge incited Timothy McVeigh to commit mass murder in the famous Oklahoma City bombing incident.


4. U.S. Government Orchestrated 9/11 Attacks

The federal government of the United States has been accused of various conspiracies, if not monstrous evils. Perhaps the most incredible conspiracy is the belief that individuals in the U.S. government had advanced knowledge of the 9/11 attacks and deliberately allowed them to happen in order to launch the War on Terrorism, expand the police state, and broaden plans for U.S. global hegemony as envisioned by President George W. Bush's administration.

It is speculated that a new “Pearl Harbor” was needed to actualize such grandiose schemes, the start of which was the invasions of Iraq and Afghanistan. Moreover, some theorists assert that the U.S. government was in league with the 9/11 terrorists and may have set explosive charges, hoping for a kind of controlled demolition to make certain the Twin Towers collapsed. The 9/11 Truth Movement claims to know what “really happened” on that terrifying day in September 2001.


5. Apollo Moon Landings Were Faked

Since the first moon landing in July 1969, conspiracy theorists have claimed that the U.S. government faked the Apollo moon landings because it didn’t have the technology to accomplish the mission. Naysayers also assert that because the U.S. government couldn’t afford such a massive failure during the Cold War with the Soviet Union, the missions were instead shot as Hollywood movies directed by Stanley Kubrick.

Proponents of the moon landings point out that hundreds of thousands of people worked on the Apollo program, so covering up the fakery would have been even more difficult than making the moon landings! A great deal of hardware was left on the moon as well, such as the lunar descent modules. Much of this has been photographed by orbiting probes such as the Lunar Reconnaissance Orbiter. But conspiracies theorists counter by saying that NASA could have faked those photographs as well.

Nevertheless, the TV program Mythbusters in August 2008 subjected many of the hoax-related claims to rigorous scientific methods and eventually labeled all as having been “busted.” Assuming the moon landings took place — which they almost certainly did — they are regarded as the greatest technological achievement in the history of humankind.

USS Eldridge

USS Eldridge

6. Philadelphia Experiment

As the story goes, naval scientists in October 1943 in Philadelphia, PA launched an experiment designed to make a naval destroyer escort, the USS Eldridge, invisible to light and/or radar. These scientists supposedly generated a massive electromagnetic field on the Eldridge, hoping to unify the four forces of nature: gravity, electromagnetism, and the strong and weak nuclear. This Unified Field Theory is a kind of Holy Grail in the world of theoretical physics, though preeminent scientists such as Albert Einstein and Nikola Tesla couldn’t produce a satisfactory model.

But, the experiment went awry when the Eldridge disappeared and teleported some 200 miles away! Apparently, some crew members also vanished and then materialized a short time later as parts of the bulkhead. The U.S. Navy has always denied that such an experiment happened aboard the Eldridge. Interestingly, some U.S. naval ships back then and even today undergo a procedure known as "degaussing" to keep magnetic undersea mines and torpedoes from drawing to the ship.

Was this "degaussing" all that was done to the Eldridge? At any rate, conspiracy theorists claim the experiment did happen, more or less as the events described, and that the U.S. government has covered up the whole story, hoping to keep this fantastic advanced technology to itself.


7. Digital Television Transmission

Some conspiracy theorists claim that the switch to digital TV in the U.S. and other industrialized nations was an attempt by the governments to spy on everyone using miniature cameras and microphones placed in cable boxes and television sets. These techniques, similar to the ones described in George Orwell’s book 1984 would make Orwell’s “Big Brother” concept a reality.

These theorists also think that the digital signals could hold subliminal suggestions so that the entire populace could be controlled and even subverted by governments throughout the world. Perhaps, these techniques are already being used by totalitarian regimes in countries such as North Korea, seemingly the most “controlled” country in the world.


8. Telecommunications Act of 1996

The Telecommunications Act of 1996, the first U.S. congressional bill signed in cyberspace, allows megamergers of media conglomerates to possibly form monster mergers of the media. Conspiracy theorists have warned that this could affect the coverage of wars involving the United States.

One of the companies that expanded into a media conglomerate was General Electric, owner of the National Broadcasting Company (NBC). Also a cause for concern, General Electric has a financial stake in the munitions market, which creates a possible conflict of interest. Theorists claim that the U.S. Congress, which passed the bill with nary a debate, is in league with General Electric and other media conglomerates, in order to maintain control over what the media publishes about the wars in Iraq and Afghanistan. Conspiracy mongers also assert that if these companies control the media, then they control most, if not all, of what the public knows about American incursions into other countries. Of course, they might control considerably more as well!

Road to Area 51

Road to Area 51


9. UFO Conspiracy Theory (Area 51 and Men in Black)

This conspiracy theory may be the granddaddy of them all, stressing the very mythology surrounding UFOs, aliens, clandestine U.S. military bases, and extraterrestrial technology.

Conspiracy theorists allege that the United States government not only has captured and housed extraterrestrials in places such as Area 51, but also conspired with them in the abduction and manipulation of U.S. citizens. One suggestion is that aliens gave the U.S. the transistor in exchange for alien dominance. The enforcers of this covert operation are known as the dreaded Men in Black, who silence those who ask too many questions about alien encounters and abductions. The origin of this unknown and mysterious organization coincides with the Roswell flying saucer epic, which inspired a movie of the same name, as well as episodes of the TV show, The X-Files. This theory also links with the Philadelphia Experiment and the Montauk Project, both of which supposedly conducted experiments in psychological warfare as well as time travel.


10. Secret Organizations Control the U.S.

Seemingly, for hundreds of years, or maybe longer, numerous secret societies or cabals have tried to dominate the world, or at least its central financial system, to deliberately cause inflation and recessions and to manipulate currencies.

For instance, the so-called Zionists are supposedly bent on controlling the world, as are the Illuminati and the Freemasons. These putative clandestine groups may be comprised of the owners of private banks, particularly ones involved with the Federal Reserve System of the United States. Perhaps the Bilderberg Group, a private annual conference comprised of delegates from the United States and European countries, may be engaged in something more than “atlanticism,” as they refer to it. Of course, the secret organizations about which we know absolutely nothing are the ones that may actually be dangerous!

HIV virus

HIV virus

11. Artificial Diseases (AIDS and Ebola)

Some conspiracy proponents think HIV/AIDS was passed from monkeys to humans in the 1930s, while others think the CIA created HIV in the 1980s, a time when HIV/AIDS became a scourge of young people engaging in unprotected sex and people accidentally given tainted blood transfusions. In those days, AIDS was an acutely fatal disease. And, contrary to conspiracy enthusiasts, scientific evidence shows that HIV originated in central Africa in the late 1800s to early 1900s.

Many folks believe that pharmaceutical companies have produced HIV/AIDS and perhaps Ebola as well, in order to reap the rewards of charging exorbitant prices for treatment drugs. Moreover, some conspiracy buffs assert HIV doesn’t cause AIDS; they think poverty or promiscuous sex or illicit drug use - or even the drugs used to treat HIV – are the real causes of AIDS. Astonishingly, contrary to modern science, Thabo Mbeki, former president of South Africa (1999 to 2008), is a promoter of this HIV/AIDS denialism.

Climate change temperature map

Climate change temperature map

12. Climate Change Proponents vs. the Deniers

This conspiracy is a battle of conflicting beliefs – those who think global warming or climate change has been caused by human activity since the dawn of the Industrial Revolution vs. those who think climate change is nothing but a hoax. The former think greenhouse gases need to be greatly reduced, while so-called green technology replaces industries that burn hydrocarbons, thereby reducing greenhouse emissions such as carbon dioxide.

Even though the scientific consensus throughout the world is that the planet has warmed at an alarming rate in recent decades, the climate change deniers or skeptics, want to continue burning fossil fuels until they think the science behind climate change is much more believable and compelling.

Of course, both sides of this environmental issue have much to gain. The creation of green energy, using wind, water, wave or solar, is a growing billion-dollar industry, while proponents of hydrocarbon-burning industries, particularly those generating energy, want to continue operating for decades, if not centuries, reaping massive profits.

Sandy Hook Elementary School

Sandy Hook Elementary School

13. Sandy Hook Mass Shooting

Conspiracy theories have even touched the heart-wrenching mass shooting at Sandy Hook Elementary School in Newton, Connecticut, where on December 14, 2012 a very disturbed young man named Adam Lanza shot and killed 20 young children and six adult staff people.

Conspiracy mongers think it was a staged event designed to provoke gun control legislation by the political left. David Duke, former Ku Klux Klan leader, thinks Zionists killed those kids, while radio show host Alex Jones thinks actors were hired to produce the event. Pundit Rush Limbaugh asserts that Adam Lanza was influenced by the Mayan Calendar event happening at the time of the massacre. Could Lanza have wanted to create an apocalyptic event that would equate with the Mayan phenomena?

Osama bin Laden's hideout in Pakistan

Osama bin Laden's hideout in Pakistan

14. President Obama and the Death of Osama bin Laden

Former president Barrack Obama has been accused of committing scores of crimes, perpetuating cover-ups and being involved in many plots, hoaxes and conspiracies. Perhaps the most bizarre conspiracy theory is that Obama didn’t have Osama bin Laden (OBL) killed in 2011, because the US had already killed him in 2002 and then cryogenically froze his body; or OBL is still alive and being interrogated by the CIA and other intelligences services; or that Obama had the Pakistanis snuff OBL because he’d helped the US government attack the World Trade Center and Pentagon in 2001 and needed to be silenced once and for all!

Proponents of this theory point out there’s no physical evidenced that OBL was assassinated by US special forces—no photos, bloody clothing, videos or the results of DNA testing—and no corpse of OBL was ever shown by the US (OBL’s cadaver was reportedly buried at sea soon after his death). Also, the raid on OBL’s hideout was video-taped by the helmet cams of the Navy Seals; but there’s a 25-minute blackout in the videos that’s never been explained, so no bullet by bullet video taping of the killing exists, apparently. However, Republican senator Jim Inhofe said he saw photos of OBL’s bullet-riddled corpse and stated, “It was him—he’s history.” Of course, photos can be doctored.

In 2015, journalist Seymour Hersh published a 10,000 word report stating that Pakistan had captured OBL and had held him under house arrest since 2006, and that the Pakistanis helped the US kill OBL in the aforementioned raid. The Obama White House, however, said Hersh’s story was false. Moreover, it’s never been proven that Pakistan helped the US kill OBL.

Coronavirus, Covid-19

Coronavirus, Covid-19

15. Origin of the Coronavirus, Covid-19

There’s nothing new about end-of-the-world stories. The world of fiction has provided many of them: The Eyes of Darkness (1981) by Dean Koontz, The White Plague (1982) by Frank Herbert and The Stand (1978) by Stephen King. And now that the Coronavirus Covid-19 has spread throughout the world, the media is rife with conspiracy theories regarding the origin of this very contagious disease—but people would also like to know if the disease was spread for some sinister purpose!

According to Snopes, authorities report that Covid-19 came from Wuhan, China, in late 2019, having spread from animals—perhaps bats—to people, as the SARS Coronavirus did in 2002. Curiously, Wuhan has both a live animal market and, seven miles away, a laboratory dedicated to handling the planet’s deadliest pathogens. Could Covid-19 have accidentally—or purposefully—spread from a lab that has allegedly produced bioengineered germ weapons?

This possibility begs the question: Why would a country such as China spread such a horrible disease? It seems spreading this virus could greatly damage the economies of many countries and even cause a political collapse of some governments, leading to sporadic violence or considerably worse. At that point, China could become the dominate power in the world—assuming it hasn’t done so already.

Then again, since the virus was present in the US in January 2020, if not before, maybe the federal government wants to cull the population of its old people—the ones most vulnerable to Covid-19—because doing so could save billions of dollars in healthcare costs. Or maybe aliens from another star system spread the virus to depopulate the earth and thereby allow greater ease to make it one of theirs.