UFOs, if they are spacecraft, are proof that humanity is not alone in the galaxy. The Search for Intelligent Life in the Universe is fraught with difficulties. First, we have yet to clearly define exactly how one can determine what creature possess intellence and which do not. Would we recognize an alien intellence being, if he didn't look humanoid.  As Captain Kirk of the Starship Enterprise (of Star Trek fame) observed while on Earth in the Twentieth Century, “Beam me up, Scottie.  There’s no intelligent life down here.”  

Typically, any “Search for ExtraTerrestrial Intelligence” (SETI) is looking beyond Earth for evidence that there’s a form of intelligent life of which we’re not yet aware.  This in turn involves two questions:  1)  Is there intelligent life beyond Earth? and 2) If so, what is the nature of that intelligence?  

A clear majority of Americans and/or Europeans believe that yes, there is something out there.  If you then add anyone believing in a supreme being, angels, divas, gods and goddesses which derive from or spent most of their time off the planet, then by definition, all of these people believe in extraterrestrials.  (And probably inter-dimensional beings.)  Finally, there are the stories of the Sumerian Anunnaki as told by the author Zecharia Sitchin in his Earth Chronicles which claim that thousands of years ago extraterrestrials spent an inordinate amount of time on this planet, influencing the development of human beings and in general violating science fiction's  "Prime Directive" to not interfere with less developed planets..

What is the nature of that intelligence?  Many believe that the gods and goddesses of legend are really alien visitors. This being the case we have detailed descriptions from through out the world, including their dysfunctions, archetypal characteristics, and rivalries. 

Given the nature of the Anunnaki, et al, of which we know about from our histories, this does not necessarily imply that we know a great deal (or even anything at all) about other species of extraterrestrials.  What about the Sirians, the Pleiadians, the Orions,  the Grey’s, the Reptilians, the Morks.

A question that is particularly relevant is what is the current evidence of visitations?  

One portion of the answer lies in the subject of UFOs ( “Unidentified Flying Objects”).  And therein lies a real can of worms (pardon the possible pun).  But if the so-called “Disclosure Project” has any merit -- and there seems precious little evidence to suggest it is legitimate -- then the human race is in contact with extraterrestrials on a continuing basis of “Close Encounters of the Third Kind.”

There are also events and on-going experiences throughout the world, which are not easily explained by anything other than an assumption of someone (possibly extraterrestrial or extradimensional) who is operating with something beyond state-of-the art technology (or at least technologies which are not known to Popular Science, Popular Mechanics, or other unclassified sources of information. 

There is also an enormous effort by various earth-based governments to write off any hint of extraterrestrial involvement in the affairs of mankind.  This is obviously in their best interests in that if it were generally known that extraterrestrials are at the door waiting for an invitation to enter -- complete with their potentially enormously better technology, all of which could be used to greatly improve the quality of life on Earth -- then what power would any government have?  It’s like your older brother trying to impose his will upon you, when  you know it’s just a matter of getting a parent’s or other adult’s attention to put things in perspective for “Big Brother”.  

Curiously, the US government has somewhat let out of the bag the proverbial “cat” (who, considering the attitude of cats toward their “masters”, are probably extraterrestrial gods and goddesses, themselves).  The kink in the government’s armor against the very idea of UFOs and extraterrestrials is contained in what is known as Space Law.  If, for example, the idea of extraterrestrials is so far-fetched (as the “authorities” would have us believe), then why are there literally laws on the books forbidding contact between humans and extraterrestrials?