Even though there are indications that UFOs have been around since the earliest memories of mankind, they have only received media attention since Kenneth Arnold saw - what the media called - a flying saucer in June 1947.
Approximately two weeks later, in early July 1947, a clear example of the UFO cover-up would become public, when one or two crafts crashed in Roswell, New Mexico. On 8 July 1947, the information officer of the 509th Bomb Group at Roswell Army Air Field issued a press release that the military had recovered a flying disc. But the very same day, Brig. Gen. Roger Ramey stated in Washington that the press release had been a mistake. There was no disc, only a weather balloon.
The cover-up as a policy
That there is a deliberate strategy within the US to cover up information with regard to extraterrestrial intelligence can hardly be denied, as the policy is formulated literally in at least two official documents. As such the cover-up is more easily proved than the extraterrestrial presence and therefore indirectly corroborates the actual presence.
The two documents mentioned above are the Durant Report of the proceedings of the Robertson Panel and the so-called Brookings Report.
A first document to recommend a cover-up is The Durant Report of the proceedings of the Robertson Panel of 17 January 1953. (The official name is the "Report Of Scientific Advisory Panel On Unidentified Flying Objects Convened By Office Of Scientific Intelligence, CIA." A copy of the full text can be found online at http://www.cufon.org/cufon/robert.htm).
The Panel further _concludes_:
a. That the continued emphasis on the reporting of these phenomena does, in these parlous times, result in a threat to the orderly functioning of the protective organs of the body politic.
We cite as examples the clogging of channels of communication by irrelevant reports, the danger of being led by continued false alarms to ignore real [BLACKED OUT-] indications of hostile action, and the cultivation of a morbid national psychology in which skillful hostile propaganda could induce hysterical behavior and harmful distrust of duty constituted authority.
4. In order most effectively to strengthen the national facilities for the timely recognition and the appropriate handling of true indications of hostile action, and to minimize the concomitant dangers alluded to above, the Panel recommends:
a. That the national security agencies take immediate steps to strip the Unidentified Flying Objects of the special status they have been given and the aura of mystery they have unfortunately acquired;
A second document is the Brookings Report which also explicitly recommends on p. 216 that "such information (...) be withheld from the public." (The official name is the "Proposed Studies on the Implications of Peaceful Space Activities for Human Affairs").
So here we have two documents that clearly consider knowledge of an extraterrestrial presence as dangerous, as a threat to national security, and therefore explicitly recommend that actions should be taken to withhold such information from the public. And that's what happened: it was decided that information about extraterrestrial intelligence, including about UFOs, should be withheld from the public at all cost. This gave rise to a whole series of covert projects, all designed for the same purpose: to cover up any such information. - See 'Secret Projects' for more information.
'Plausible deniability'was a key strategy to that end.
A possible third document that confirms the existence of such a policy is the 'Eisenhower Briefing Document, whose authenticity is disputed. It states, e.g.:
Implications for the National Security are of continuing importance in that the motives and ultimate intentions of these visitors remain completely unknown. In addition, a significant upsurge in the survejl1ce activity of these craft beginning in May and continuing through the autumn of this year has caused considerable concern that new developments may be imminent.
It is for these reasons, as well as the obvious international and technological considerations and the ultimate need to avoid a public panic at all costs, that the Majestic-12 Group remains of the unanimous opinion that imposition of the strictest security precautions should continue without interruption into the new administration. At the same time, contingency plan MJ-l949_O4P/7 (Top Secret - Eyes Only) should be held in continued readiness should the need to make a public announcement present itself. (see Attachment "G".)
Reasons for the cover-up
The Roswell incident taught us that the cover-up as a policy was already in place in 1947. At the time the Cold War had already started and there was a real danger of a third world war erupting. In those circumstances nobody thought it wise to acknowledge that Earth was being visited by extraterrestrials with a technological knowledge that exceeds ours by far. There was a genuine fear for the public reaction: in the short term, there was a fear of panic and public hysteria. In the long term, there was the fear that such knowledge might actually lead to the disintegration of society. Experts therefore explicitly advised that such information be withheld from the public. And that is how the cover-up started (See , e.g., the 'Brookings Report, quoted above and below' for more information).
Over the years, a situation came into existence that led to additional reasons why the cover-up was maintained, and to this day still is in existence.
The following list was inspired by Dr. Steven Greer's list of reasons why the cover-up is maintained. Some items have been added.
Fear for the short-term public reaction: public panic, mass hysteria and social disruption
Recent natural disasters come to mind that were followed by a temporary state of lawlessness resulting in looting, rape, etc. The fear is that a public panic might occur in case of a sudden disclosure, which would then result in possible mass hysteria and social disruption. Or, as the above quoted Durant Report put it, "result in a threat to the orderly functioning of the protective organs of the body politic."
Fear for the long-term public reaction = fear for the disintegration of society
The Brookings Institute famously warned, on p. 215 of the above mentioned report, that "Anthropological files contain many examples of societies sure of their place in the universe, which have disintegrated when they had to associate with previously unfamiliar societies espousing different ideas and different life ways; others that survived such an experience usually did so by paying the price of changes in values and attitudes and behaviors."
Security issues surrounding possible military and technology applications of ET technology
What could terrorists or hostile nations do if they got their hands on free energy devices, on extraterrestrial craft, on extraterrestrial weaponry, etc.?
Uncertainty and mistrust regarding ET motives and ultimate intentions
We don't really know who all is out there, nor what their intentions are.
Embarrassment and consternation over human military inability to secure world air space from repeated penetrations by ET craft
At present, our technology is no match for extraterrestrial technology. The military and the politicians will be reluctant to admit that they cannot control who enters air space, nor can they control what these extraterrestrials do (as abduction cases seem to confirm).
This notion of "we may not be able to defend ourselves" would also contribute to the possible mass hysteria, mentioned above.
Embarrassment and loss of face resulting from disclosures concerning how this matter has been handled, such as the harassment and ridicule of innocent civilians and military personnel, the withholding of information from the public and Congress, etc.
Greer rightfully mentions the possible embarrassment of the key players involved in the cover-up. Personally, I think it goes further than that:
Possible liability of the involved players
A lot of things have been going on over the last 65 years that clearly were unconstitutional, and in many cases even criminal. It is understandable that those in charge of the cover-up would oppose disclosure if this means that they were likely to face criminal charges.
Effect on global economy
Apart from that there also is the direct impact on the industries that are involved in the cover-up itself. To put things in perspective: an estimated 1.7 trillion dollars - or more - is invested annually in covert operations that involve extraterrestrial technology in the US alone.
It is therefore safe to assume that one of the main reasons for a maintained cover-up is that disclosure will have to be organized in a gradual way (step by step) in order to not disrupt the global economy too much.
It may also be useful to point out that many political decision makers have vested interests in the industries that currently benefit from the cover-up.
Effect on special interest groups: religious, economical, military...
Last but not least, there are loads of interest groups who benefit from the cover-up, be it directly or indirectly. These groups tend to be quite influential.
In my view, these are the most important reasons for the cover-up and for maintaining it. A more comprehensive and extensive list was compiled by Grant Cameron, and can be found at his web site: www.presidentialufo.com/old_site/ufo_coverup.htm.
This topic was largely copied from www.exopoliticssouthafrica.org/disclosure.htm
Several researchers, like e.g. Stephen Bassett, are not happy with the term UFO Cover-up. On the one hand, it is not just information about UFOs that is being kept from the public. It is wider than that and applies to an extraterrestrial presence that has been here for millennia, and has been engaging humankind for all that time. A second reason is that the word cover-up has connotations of being illicit. The reasons mentioned above for keeping this information from the public could all be valid, and the people who are involved could therefore very well be convinced that they are doing the right thing. That is why Bassett launched the term Truth Embargo.