I am currently reading Peter Dale Scott's new book, "The Road to 9/11," and I am enjoying it immensely. It gives an excellent overview of ruling-class warfare of the last 40-50 years. Institutions such as the American Security Counsel and the Committee on Present Danger are mentioned and divisions between figures such as Brzezinski and Carter's Secretary of State Cyrus Vance are elaborated on. I was surprised to read that James Angleton literally believed Henry Kissinger to be a Soviet spy.
Scott discusses the Office of Policy Coordination, the CIA's hidden operations section in its early years, and one of its first initiatives, the creation of and support of "stay-behind" networks in Europe, including Gladio in Italy. One of its authors was Guido Giannettini:
Guido Giannettini, on of the Italian authors of this strategy of tension (and of the Piazza Fontana bombing eight years later), came to America in 1961 to lecture at the Naval War College on "Techniques and Possibilities of a Coup d'Etat in Europe." In March 1962, the Joint Chiefs of Staff prepared their own documents developing on Giannettini's strategy. This was Operation Northwoods, which many books have cited as a "precedent" for "US complicity in the attack of 9/11."
Unfortunately, the source of this information is an Italian language book called Piazza Fontana by Fabrizio Calvi and Frederic Laurent.