I have read quite a lot of UFO writing over the years.
The reason I haven't blogged about it is that I don't have a great deal to say on the matter. But yesterday somebody asked - so here goes.
I don't rule out that - at some level - the UFO phenomenon is, or was, genuinely 'paranormal' and purposive. Yet I somehow don't regard the matter as very serious or significant - at least, not unless an interest in UFOs was to lead-onto a more spiritual way of thinking and living, as happened with John Michell (Michell's first book was about Flying Saucers).
My main hypothesis is that UFOs are part of the spiritual warfare between angels and demons; and how this is manifested to certain people in certain circumstances. However, the matter is of UFOs nearly always discussed in a materialist (and unChristian/ anti-Christian) context. In other words, some UFO phenomena are probably angels (or made by them) while others are demonic.
But UFO appearances do not seem to be a very effective method of spiritual intervention - at least not for the angels. Why would angels do such a daft thing? Well, I regard angels as fallible creatures - being not a separate creation from Men, but pre-mortal and resurrected that are Men active in earth life. That is, angels are the not yet born, and the so-called-dead. Such angels are doing their best and learning from the experience; but it is inevitable that some of their ideas will fail to achieve their intended results - and maybe UFOs are an example?
UFOs, when they originated in the late 1940s, might have been modern miracles; spiritual manifestations designed to break the belief in materialism. For example, the Fatima miracles of 1917 would probably have been interpreted as UFOs if they had occurred in 1947*.
So what may be happening with UFOs is that spiritual phenomena of light (with its ancient symbolism of divinity) were misinterpreted materialistically; as high tech spaceships piloted by aliens. Then demons (who are pre-mortal, un-incarnated-spirit Men that are actively opposed to God, Good and divine creation) may have exploited this situation; and engineered other manifestations and contacts, in order to reinforce a world view that favours their evil agenda.
This is just a vague idea, and I don't have much interest in making it more precise; but it is part of my more general understanding that modern people are so deeply and habitually materialistic; that they will reduce anything spiritual into this framework.
Many millions of people very quickly developed strong and detailed beliefs in alien existence, contact, communication and plans that were based on no more than hearsay and dishonest mass media accounts, or (more rarely) on very ambiguous personal experiences of strange phenomena.
And this happened at such a large scale and so rapidly, because modern people find aliens possible (no matter how unlikely); while angels (and demons) are ruled-out a priori - because the metaphysical Christian beliefs that make sense of angels and demons are nowadays (generally and officially) regarded with bored disdain or loathing.
*Indeed, pretty much all the ancient supernatural events of the Christian Bible, and records from other religions, have (at one time or another in the UFO literature) been re-re-interpreted and explained as early examples of interactions between humans and various combinations of alien beings, alien-advanced technologies and flying saucers. Either this - or the opposite mainstream Establishment attitude of complete rejection, mockery and denial - is how a metaphysics of extreme and convinced materialism inevitably deals with anomalous phenomena.