UFO Incidents & Disclosure:

1947, Project HighJump with Admiral Byrd
Allied military expedition (4700 men, 13 ships and 33 aircraft) to Antartica.
Conflict/battle between Allies & UFO's, lost by the Allies

March 24, 1967, Montana: 

UFO deactivated Nuke Base with 10 missiles:

United Nations on September 21, 1987:USA President Ronald Reagan talking about "Outside Universal/External threat!!"

"Foo Fighters" or The Nazi Bell during WW2: