The C.I.A. classified a 284-page book on earth's catastrophe cycle and crust displacement in 1966.
With the focus and publicity of the topic at the time, why classify THIS one, wait so long to release it, and so-heavily sanitize the document down to 57 pages?
Read the document for yourself:
https://www.cia.gov/library/readingroom/document/cia-rdp79b00752a000300070001-8
A little bit of knowledge
Can be a dangerous thing
Or it can be a vibrant seed
Giving rise to verdant forests
And awakening sleeping giants