Enrico Fermi's paradox is swallowed easily as soon as you realize alien existence does not have to involve alien intelligence making actual contact or even detectable alien presence. Nevermind the fact that every radio pioneer before Marconi claimed they received intelligent transmissions: every paranoid schizophrenic knows those are stunts pulled by British MI who had that technology for centuries. Francis Bacon wasn't just making up Rosicrucian telepathy claims in the New Atlantis - he was making technological statements.
( And of course Egyptians knew electricity and the Assassins are the link in the chain that connected British Freemasons with electrical secrets through the Knights Templar. But of course! You clearly must have been the victim of communist indoctrination at school. Next thing I know you'll be telling me human civilization is less than 10,000 years old. )
As TekkonKinkreet and Saige put it, the paradox actually concerns advanced civilizations capabilities of piercing the veil of long distances searching for signals of life: electromagnetic, water, air, organic chemicals and so on. And they could easily do that undetected supposing they can either travel FTL or image FTL.
General Wesc raises an important point: really
advanced civilizations would also search for the
stuff of other kinds of
intelligent life that we aren't aware of. And
maybe there's even a way to know beforehand where it will eventually develop, you know, through
time manipulation? That introduces yet another philosophical question in the
trekkie tradition: if their models show possibility of
negative entropy molecular machines self-assembling, do they meddle with it? Game it a little, perhaps? It's a far more interesting question than the moot point of the original paradox, due to the
invisibility question.
Maybe they miss the heroic transmissions darkened by fiber optics. They could search and search and hardly find more intelligent television. I do hope they are helping our helpers through coincidence control.
As Karl Marx would have put it after reading Charles Fort and being visited by Men In Black: We are the cattle of our future selves. Oh yeah, that already happened and that old weasel is Robert Anton Wilson. Therefore, you will find intelligent life - Level 2 Civilizations - inside wrongly understood "black holes", "binary star systems" and the like. I doubt such advanced characters would waste their time giving you anal probes.
Definitely the worst part of this overhyped "paradox" is that it leaves room for deep black shady government syndicates deciding to stage a world government coup after major disaster strikes. You know what I'm talking about, the Watchmen scenario meets Rael and all of a sudden the peaceful wise beings from outer space show up with their UFOs everywhere to help bad bad stupid mankind. You can bet my guerrilla comrades will be testing if Riconosciuto's a-neutronic bomb can down UFOs. I bet it can.