According to Wikileaks Stratfor UFO files, among all the controversial documents leaked to the public in the last twenty years regarding state secrets and the UFO phenomena is the fantastic revelations of the CIA's unacknowledged MJ MAJESTIC TWELVE files disclosing the most guarded of all classified subjects-extraterrestrial life forms and their technologies.
In order to secure this knowledge and prevent foreign countries from learning this vital secret and get an edge on the United States, President Harry S. Truman signed a finding that basically said that no one (including a chief executive) was to be in possession of, or disclose the finding without a "need to know" clearance which was above Top Secret.
