there is no such thing as ufos and aliens

it would not be possible to keep this a secret for so long, simply not possible. Even if one country somehow could for the best part of 80 years - the other 100+ countries would not.

we probably cracked antigrav or some form of new propulsion years ago and UFOs are just a cover up - if there is any slight truth to the topic at all (pilots seeing things in restricted airspace)

otherwise there is nothing to this topic at all - just another religion