After all, in the Nuclear Age the true enemy cannot be destroyed which is the nature of war and the missiles and their technology. I feel these aliens have a soul or are demon-possessed because demons cannot influence mankind very well without a body. I feel that now that they have a body, and a potentially infinite weapon of destruction or travel, which are the awesome and powerful flying discs themselves. The bible says that demons will walk with men on earth some day. Believe me, if they are smart enough to build the ultimate high-tech interstellar craft, they certainly could give us all sorts of medical and technological knowledge.
Demons are smarter then men.
They have powers that we do not fully understand or even know about. Just imagine the facility that it would take to built a flying saucer. I feel these aliens have been coming here for thousands of years. They are not something imaginary or fictitious. They seem to be gathering massive amounts of data on us.