This makes me reevaluate my rule of thumb on conspiracy theories. I have to move the bar in terms of what is too ridiculous to be potentially true.
If you tell me the government has been covering up alien visits for decades, I still consider that too ridiculous to be true, but mostly for the reason that alien visitation seems unlikely. I have no problem believing that the government would cover it up for some dumbass reason. That is well within the realm of believable.
I have no problem believing that during the 9/11 attacks our government ordered the Air Force to destroy the passenger jet that was heading for the Whitehouse, and found it convenient that the passengers rushed the hijackers at about the same time. It makes a good hero story. I'm not saying that's what happened. I'm just saying that it doesn't qualify as too ridiculous to be true. To me it even sounds more likely than the official version.
The most evil conspiracy theory I have ever heard involves the idea that the 9/11 attacks themselves were planned by the U.S. government as a pretext for military action and subsequent profit by some industrialists. I don't believe that's true, but again, thanks to Governor Asshat, I can no longer rule it out simply for being too ridiculous to consider. The bar has been moved.
I don't know if the Mafia fixed the election for President Kennedy, then had him whacked because he didn't return the favor, but it is well within the realm of non-ridiculous.
What other theories do you think are now in the realm of not-too-ridiculous?