[Svartalfiar]

The problem that stems from this worry (lack of problem) is that us announcing our presence is still extremely contained. Unless these super-advanced aliens live right next door to us, it's just not possible. Aliens from another galaxy simply cannot have 'seen' us yet. Outside of faster-then-light travel / communication, even other beings in our own galaxy wouldn't have seen us yet. The only, tiny, man made objects that have left the solar system are essentially still on our front porch. Our initial radio broadcasts have barely made it halfway through the neighborhood (and at this point are weaker than the universal background noise).

[Openurmind]

What I find ironic is that we are looking for them “out there” when they have been hiding right here on our planet for at least a half million years.

[GingisK]

I don’t think they could see us once our RF racket reaches the, either. Due to that Inverse Square Law, the probability of picking up a coherent signal rather than a stray photon from time to time would be low.