This book is about how powerful economic interests, which also control the government, the mass media and academic institutions, have used scientific thought-control to suppress freeenergy technology. The UFO is only the most glaring and remarkable example. If you are intelligent enough to realize that man-made UFOs exist, then you know that "free energy inventions work", because a UFO is a free energy invention. A believer in man-made UFOs, who doesn't happen to share a belief in space aliens as the responsible-or even the partially responsible-parties, is made to feel uncomfortable when among those of a UFOlogy gathering, sort of like an Atheist at a fundamentalist Christian revival meeting, or a microbiologist at a witch-doctor convention.
That is an interesting book on ufos, that has the thesis that Ufo's are man made technology, the author apply mental gymnastics to proof his point and does not take in consideration that the phenomena is a USA only phenomena and it is not happening through the world. It also states that the free energy technology is suppressed by the government, it is a version of some of Vallee positions, the author does concede that he suffers from some health problems. I tend to mostly disagree with the premise but I had the patience to read it all.