I found this book to be a good take that avoids hyperbole and tries to stick to the evidence and facts:
If you were to ask me to guess, my bet is that current and past government programs to investigate these objects have concluded that a) they are non-threats to US national security and that b) performing further invasive means to investigate them past our current level of understanding is too risky to pursue. So (again if I had to guess) the consensus is, theories of their origin aside, "don't look into it further, and be assured that there will be no harm in not doing so," which is why you can see a program like this shut down without necessarily assuming that it was a waste or a wild goose chase.
In a field where many of the books are written by either true believers or debunkers, this is a fresh take on the phenomena, carefully researched and conservatively written by an investigative journalist.
It's a very good read. Also, in all UFO threads there should be a disclaimer that you are not making a point by pointing out that UFO stands for Unidentified Flying Object not Alien Spaceship; most people when referring to the truly unexplainable cases use them interchangeably since extraterrestrial origin is one of the few hypotheses that are consistent with the evidence, though it's never obviously conclusive.
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