Up to a few years ago, no one in the scientific world would even suggest that aliens exist somewhere out there. It would have been a career suicide. Today, it’s generally accepted that, mathematically-speaking, the probability of intelligent life out there is extremely high.
So where these aliens are then?
I’d like to believe they’re here. Simply because the opposite is too scary of a thought. If they’re not here, it’d mean that WE would NEVER be able to leave our solar system either. This means eventual death, since our species only thrives via expansion.
If on the other hand, there is a way to trick the natural laws and travel in vast distances (e.g. via wormholes), then that would mean that aliens ARE already here. Or have been here.
And honestly, I believe that the second hypothesis is true. The first one somehow makes no sense to me. Having no way to connect with others elsewhere, it would mean that this universe has a… bug in its design. That’s how I see it.
So, if these aliens are or were here, where the heck are they? Why are they hiding from us?
I think Star Trek has given a great explanation about this. According to the show’s Prime Directive, it’s best for each civilization to only be contacted once they have achieved “warp speed”. A similar Prime Directive possibly exists in this galaxy too, but I think that their rules aren’t about warp speed: it’s about proving that the civilization is not self-destructing. A self-destructing civilization means it’d be violent against other civilizations.
It seems logical to me that every single society that achieves technology, goes through what we’re now going through: massive man-made climate changes, exhausting and destroying the environment, life quality degeneration etc. We’re currently on the fast track to extinction, and THIS century is the MOST CRITICAL century in the history of the human kind. It’s a make or break century.
If we use common sense, we change our ways and we survive, then these alien civilizations will reveal themselves. If we do get self-destruct, then there was no point for them to make an effort to reveal themselves anyway. It’s not their job to save us, it’s ours. Their only job is to safeguard themselves and their allies. So it’s up to us to become galactic citizens, or return back to the caves.