At the height of the Cold War, the Pentagon and CIA were more than happy to let the public think unusual sights in the sky were caused by natural phenomena, not by secret aircraft they were developing. The possibility of aliens landing in the desert West also worked, the New York Times reports, to deflect from secret efforts by the Air Force and CIA to develop the capability of greater Soviet reconnaissance. But the CIA, at least, later had second thoughts. "The agency's understandable interest in concealing its role in some of the early UFO investigations ultimately proved to be counterproductive," a 1997 CIA report said, adding that "it just fed into later charges of conspiracy and cover up." The government could change direction this month, when it releases a report on the possibility of UFOs and aliens.
The CIA worried then as now about the effects of Russian disinformation on the American public. The fixation on aliens could bring the wrong response in the event of a Soviet attack; Americans might swamp officials with alien invasion reports instead of taking shelter from an earthly threat. In some cases when UFOs—which the government now refers to as unidentified aerial phenomena—have been reported, government officials have been relatively open about what was going on, per the Times. But other times, they haven't been, to protect the secrecy of various military programs, leaving room for conspiracy theories to thrive. "Government secrecy has acted as a spur toward conspiratorial thinking, and it has aggravated that tendency in some sectors of the American public," said Steven Aftergood, a government secrecy expert for the Federation of American Scientists. “It's not just limited to UFOs." (Read more UFOs stories.)