Meh... and of all the thousands of people that have known this vital secret, how have they been able to keep that under wraps? Why would they? Something with that widescale of an implication would find a way to get out IMO. As the people who know about it are getting old and gray and fading, and with all the millions of people out there looking to pick up a story and run with it, and all the ways to get things broadcast on the internet, it would find a way out. And I seriously doubt the whole world is keeping their lips zipped because they're worried that the Americans might flip out if they announced ETs are real.
I just don't buy the grand conspiracy.
Also, if ETs are ON EARTH for the past... hundred or more years, they're not going to be bothered zipping around Shanghai airport to confuse people with twinkling lights. If an ET were here in THIS solar system, then either this plant would be hostily taken over long ago OR we'd have learned something from being with near light speed transportation and not be wasting our time with oil! I dont think they'd be here for kicks to confuse people with an "unexplained" light show here or there.