Mr. Seeley, either you didn't read the article or misunderstood it. Greer is part of the choir here. He is turning the term "National Security back upon itself"...embedding it in a positive way into its own self-destruction.
While the PowerMongers say we must NOT be told for the sake of 'National Security', Dr. Greer says that by not telling the public about the entire UFO scenario, the PowerMongers themselves are creating a problem of 'National Security'.
He uses their own terminology to MAKE them wrong.

To call Dr. Greer an 'imperial flack' is mean-spirited and rather ignorant on its surface. "Ye shall know them by the fruits of their labors..." I would say Dr. Greer's 'fruits' are looking pretty good. ...perhaps you just need to read the article...
Smiles,
E.