Have there ever been any conspiracy theories that turned out to be true?

Roswell. And the moon landing.
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9/11
Look into tower #7
didnt believe the conspiracy yapping dogs before I actually researched it myself, mostly its the lack of destructive force and how fast all towers fell but there are many reasons why if you look, you will agree, it was not airplanes that made the buildings fall.

edit:
Come to think of it.. theres probably quite a few of them
Agent orange during vietnam
water gate
deep throat
W.M.D.s
and those were just the ones in the media… = [

But people like their perspective, if they didnt, they would probably research it themselves.
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Many people are likely to post here with their own favourite unproven conspiracy theory, which will no doubt be useless to you in trying to convince your parents. Here are some real occurances which were originally considered to be conspiracy theories:

A famous scandal which began as a conspiracy theory was the Watergate affair. It began as a conspiracy theory about a hotel break-in, but ended up being traced to the highest levels of the American government, and it forced the resignation of President Nixon.

Other real conspiracy theories include:
- the French government's cover-up of the Dreyfus affair,
- Operation Himmler, where attacks were faked against German soldiers on the Polish border to justify the 1939 invasion,
- MKULTRA, the CIA's attempt to create and use mind control drugs,
- Operation Northwoods, again the CIA, this time committing violent acts which were then blamed on Castro
- Iran-Contra, where weapons were sold illegally to Iran to finance anticommunist rebels in Nicarauga
- the Tuskegee Study, where African-Americans were deliberately made unable to access treatments for syphillis to see the long-term effects of the disease
- the Streetcar Conspiracy, where GM and other auto industry companies began secretly purchasing streetcar lines, dismantled them, and replacing them with buses.
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If it is a consipiracy theory than it has not been proven to be true. If it has been proven then it is a fact. Right?
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I should probably take a breath, relax and do some more research before posting but hell no - I’m at work and have not time so here is off the top of my head “no longer theory” but moved on towards something of being denied but everbody knows they are lying…..;
Jonestown Massacre in Guyana - Oh Yes was this one not very quietly brought to a rude conclusion with the CIAs wrap-up ensuring that certain people would never be able to testify - talking about thier actual armed presence at the final hours - no disputing and this was just another one of the MK Ultra typemind experiments that became public and scary - The TOWER 7 stuff - you do not find a single sane Engineer willing to dispute the filmed evidence there PERIOD. - and; Jack Ruby’s death in PRISON - Jack Ruby’s easy access to Oswald… why on earth would Jack Ruby give a hoot about Oswald anyway..!? duh.
and of course; The woman being torn down and abused on tape by her INTERVIEWER to get her to say “”I did NOT hear those two people who scooted past me on the stairway say ‘we just killed Bobby Kennedy’”" as she continually asserts that that was exactly what she saw and heard - he persists for HOURS tryiig to get her to say “I DID NOT see/hear anything of the kind” she refuses and he relents- - now why was it so important to a LAW ENFORCEMENT person investigating a murder to harrass this person in order to get her to say the opposite of what she saw - and to ensure NOBODY put out an APB on the two people she witnessed at the scene - until you find out the INTERVIEWER was a Doctor invloved in Mind Control and hypnosis work for the Government (publicly)
or;
the attack on the USS Maddox and USS Turner Joy that gave LBJ the green Light to attack North Vietnam without any Congressional declaration of war(The GULF of TONKIN Resolution… and of course The most glaringly obvious set of illegalities ever to be called Conspiracy Theories when in fact the whole freakin sequence of painfully illegal occurances were NEVER theoretical at all - and that would be of course the already mentioned IRAN-CONTRA “affair” - OK it was a whole helluva lot more than those 2 words Iran Contra it was illegal funding of terror and death squads all over CENTRAL America not just the Contra “Rebels” in Nicaragua - it was DRUG TRAFFICKING Profits channeled to these illegal killers by our CIA - it was drug trafficking profits that included the astonishing ascension of Crack Cocaine in the ghetto becoming the most crazed drug of choice in history with community destroying effects - it was also of course ARMS sales to our most hated enemies and the direct manipulation of the Hostages in Iran whose keepers benefitted from these Arms sales so that Reagan could ensure his Election over the incumbent Jimmy Carter by not allowing the release of these long held American prisoners until Reagans INAGURAL DAY in office - many months in captivity after the deal had been done - and BNixon didn’t resign because of a little old break in - he resigned because in the investigation into the group of criminals he had working for him a whole slew of Subpeona’s were on their way towards the upcoming Impeachment Trial that could blow the whole roof off his much more harmful and illegal Executive Branch shenanigans that could alos be traced all the way back to his loss to JFK in 1960….