Conspiracies, JFK/9-11: Grassy Knoll shooter confesses
For those unfamiliar, this is the relatively recent, recorded confession with correlating information supporting the case that JFK was murdered by a CIA/Mafia cadre.
These are just introductory links where there are numerous articles & videos online by the researching author, Wim Dankbaar.
While the documentation is relatively new to myself, I would estimate the legitimacy of such facts corroborates the hypothesis that a criminal operation like 9/11 is historically possible in the United States.
God bless you, JFK and many thanks to our pioneering researchers
(inc. Jim Marrs, an acknowledged 9/11 Truther)