I'm assuming no one here actually believes inteligent aliens often visit earth. But how would humanity's religions react if they did? Would it share some beliefs? Would every single one simply add a few retcon lines or interpretations to ajust? What do you think?
And what about non-intelligent life elsewhere? Would that discovery do anything?
I think it might cause some to question their beliefs; but, the truly devout will find some way to explain it, or deny it. I think the universe is too vast to actually make contact with other intelligent life; but, I do hope that we find evidence of current or past extra-terrestrial life, intelligent or not, before I die. I am not sure how it would change humanity; but I certainly hope that, overall, it would cause us to have a more humble view of ourselves.
The devout would fall on their knees. The fools would glad-hand the aliens. The wise would take note of where the aliens' eyeballs are located. If in the front of the skull, they are predatory, like us. If in the side of the skull, they are probably good for eating.
Look up the Drake equation. Imagine the tremendous effort it would take to get here after bridging all the hurdles from abiogenesis to surviving long enough to wrestle with forces that might wipe out your species. Fission for example. Now you see the Blue Marble on the horizon. You had better make damn sure you have the upper hand when want to meet these bald apes. And I'm sure they would. In that light, I would welcome our new alien overlords.
I don't believe intelligent beings from another planet visit regularly, but maybe they visited some time, long ago...is that where the many myths of gods flying across the sky originated?
I would ask them to please take all the Trumps back with them.
I might beg, actually.
Watch "The Day The Earth Stood Still", starring Michael Renie & Klatu.....