Why is the US Navy refusing to give out its information on UFOs because it would damage the USA?

(000228.79-:E-000157.73:N-:R-SU:C-30:V)   

This was my response on the social media to someone who was talking about US military film footage on UFOs and why more is not being brought into the public:

I was a huge UFO buff. Studied it intensely. But in the 1990s I learned of pilotless aircraft and that they are TOP SECRET in the Western Military. I have looked at many aspects of UFOs and I am 100% convinced these are various types of experimental or operational military aircraft. UFOs are NOT ALIEN. Not from space. They are 100% military. They are also not “flying saucers” of the past. They are merely, new designed pilot-less planes. Most are for spying but they could have other roles including bombing. They might also be planes for experimental military purposes. Returning to the Navy not wanting to release info. This is because these are military things. The SR-71 for example, was so secret for decades, that the FBI made civilian airliner passengers and pilots sign secrecy documents if they saw them. That is why civilian airline pilots and passengers talk about seeing flying saucers. If they said anything else they would go to Jail. Its that simple. There’s a great documentary from 2011 in this regard about Area 51. When old CIA and other people come out to explain how they built Oxcart, the predecessor to the SR-71. In the 1950’s white men were jumping from the edge of space using balloons. USAF officers, many of them Colonels, were doing this stuff. It was 100% hushed up. But you can find the film footage.