Thank you for the link. That is one of the more comprehensive speeches Mitchell has recorded and depicts his views very well. The fact that Mitchell believes we have been visited has been around since about 1996 when he was interviewed by NBC, and several times since then. He's been on Larry King, Fox News, etc. discussing the same issues.
Mitchell has never claimed to have any first-hand knowledge of UFOs or visitations. He says he has read the same research we have and talked to the same people we have. He may have been in a better position to get insider information. At one point he talks about discussions with the 'old timers' who told him stuff. He says he talked with an intelligence official who confided in him that UFOs were real. He was friends with John Mack, who told him the abductees he studied were straightforward people and not given to flights of fancy. He told one newspaper a 'cabal of insiders' was studying alien bodies.
So although Mitchell
believes we have been visited, he is not a primary source like Gordon Cooper, for example, who said he saw a craft land in front of him and saw film being shot of the event. His own sources are deceased, kind of shadowy, or not to be named. Mitchell's politics tends to be very much like Exopolitics in that he believes there is a 'community of planets' that we must join if only we would stop being so warlike. He also has kind of a religious bent, which you an see at his Noetic Sciences site:
http://www.noetic.org/. He had a 'transformational experience' when coming back from the Moon that made him see 'all life as one' and that has guided his life since. That is very clear in the link provided above.
That may be why although he has said this stuff for nearly 15 years now, it never seems to 'take off.' Every once in awhile there is a newspaper article or an interview where he says essentially the same stuff he has been saying. He gets quoted for a few days, and then it disappears again. Like most of the astronauts, he's low-key and soft-spoken--not a fire and brimstone speaker.
Other than being famous for Apollo 14, he's actually very much like one of us. He's interested in the field. He has read the books. Once in awhile he seems to have been privy to some insider second-hand information. He's developed some beliefs about UFOs from his research and contacts. And he'd be a great guest for the Paracast.