It is not so well documented that Area 51 and other like places were created after WW2 when the US confiscated several top secret German projects and took them home to reverse engineer them. Stealth technology and flying saucers were discovered in Germany way out in heavily forested areas where no one could see what they were doing. The "UFO" hysteria was rejected but then used by the military to fool would-be whistle blowers as to what was really going on. To fool enemy nations they even created a "dumby" department to make it look more authentic (your hard earned tax dollars at work). It worked so well the Russians adopted a similar approach to covering up top secret activities.
And those "grey aliens"? They were monkeys that had their fur shaved off and sent out into the atmosphere and space so that scientists could perform autopsies to analyse the effects of space radiation on living beings before sending humans "out there".
Yes Mulder, there really was a "conspiracy" going on. Just not what everyone wants to think.
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