ok I will edit again.

This has interesting discussion regarding FM 30-31B and Operation Northwoods https://cryptome.org/cia-FM30-31B.htm

The hearing record also includes a copy of the Covert Action Information Bulletin (below) which published FM 30-31B in 1979 along with an assessment of its authenticity: "Regardless of the dispute, we believe, as do publishers in several other countries already, that the document is real, and that in any event our readers should see it and decide for themselves." CIA testimony provided a single claim for calling the document a forgery: that it was marked "Top Secret" and that field manuals are never so highly classified. There may have been other claims which were deleted from the public record of the hearing to protect classified means and methods for detecting forgeries, but if so they do not appear to have been made public. Without such other information, the single CIA forgery claim appears weak:

1. Neither the US military nor intelligence agencies fully share their most secret documents with other government agencies, much less with the US Congress. That was the case in 1980 as it is now when the Department of Defense is in a tussle with the CIA over intelligence gathering and covert activities. See James Bamford's revelation of the 1960s Operation Northwoods, a top secret plan for the US Chairman of the Joint Chiefs of Staff which proposes exactly the kind of covert action, including against the United States itself described in FM 30-31B (thanks to D. for the comparison):

http://cryptome.org/northwoods.htm [Excerpt]

Although no one in Congress could have known it at the time, Lemnitzer and the Joint Chiefs had quietly slipped over the edge. According to secret and long-hidden documents obtained for Body of Secrets, the Joint Chiefs of Staff drew up and approved plans for what may be the most corrupt plan ever created by the U.S. government. In the name of anti-communism, they proposed launching a secret and bloody war of terrorism against their own country in order to trick the American public into supporting an ill-conceived war they intended to launch against Cuba.

Code-named Operation Northwoods, the plan, which had the written approval of the Chairman and every member of the Joint Chiefs of Staff, called for innocent people to be shot on American streets; for boats carrying refugees fleeing Cuba to be sunk on the high seas; for a wave of violent terrorism to be launched in Washington, D.C., Miami, and elsewhere. People would be framed for bombings they did not commit; planes would be hijacked. Using phony evidence, all of it would be blamed on Castro, thus giving Lemnitzer and his cabal the excuse, as well as the public and international backing, they needed to launch their war.

1. The CIA's testimony appears to closely follow the CovertAction analysis to offer counters to it, point by point, but does not offer evidence, at least not in the published versions, to support the claim of forgery, only unsupported assertions.

2. The CIA is reported to engage in the same covert actions, including forgeries, of which it accuses the Soviets, and it never publicly admits to them.

3. It is a common ploy for intelligence agencies to accuse their competitors of what they do themselves when publicly exposed, to offer piecemeal explanations, pause to see if they calm a storm, then issue more as required, each time gauging effectiveness. The hearing could be seen as part of such a counterintelligence operation.

On February 20, 2005, Cryptome made an FOIA request to the Central Intelligence Agency for information on the authenticity or falsity of FM 30-31B.