I believe it is highly likely there is life beyond earth, perhaps even with our solar system. But the odds that extra terrestrial life is sentient and capable of the surpassing the scientific and engineering issues related to interstellar travel makes it pretty unlikely that they have visited here.
I think it's much more likely we'd pick up radio or video signals long before anyone visited. They'd have little reason to hide them from us.
Pentagon wouldn't hide ETs, and even if they wanted to no conspiracy holds that long. Beans get spilled. So no. Obviously it's silly.
Of course (IMO... lol) there's life out there. Intelligent life? I think the statistics favor it. What form does that take, I have no idea. Might seem pretty wild to us. Although it seems by far the most likely is carbon based.
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