I've considered many facts pertaining to the issue . Planet earth is on the outskirts of the milky way galaxy , we are so far out of the way that IMO even if there was extraterrestrial life this would be the last place in the universe they would look for life . The distance from our solar system to other likely ones is just too far and as far as man is concerned nothing can reach the speeds needed to travel those distances in a reasonable amount of time .
they never came to any hard conclusions, but one, there is something going on and there are few hard answers as to what.
there were many, not just a handful of nuts, but many who reported these sightings from commerical and military pilots [they mentioned thousands of reports that were NEVER given to anyone but bluebook [who buried them] they also had reports by military people guarding nuclear missle silo's and others who were top secret clearance types who were not given any information as to what was what....
from the program, I learned that blue book was started with only one real purpose.... stop the panic which was crippling the national communications network of the time by any means possible... since no explanations could be given with any certainty, they blamed it all on natural phenomenon even when such explanations were totally ludicrous.... the public only knew that the gov't said it was nothing to worry about and that was all that most people needed...and the panic subsided and it seemed obvious that if these things were from outerspace they were not threatening us so there really was nothing much to do other than keep blaming sightings on natural stuff....
perhaps some in the gov't really know what is going on, but I suspect they dont...but are unwilling to admit they have no clue.
as to secret military, I am sure that the black ops people dont tell the gov't everything either and so there is plausible denial