I am a big believer that if intelligent aliens are visiting us and want us to know about them, we will. If they don’t, we wont.

Any alien race that can breach the great distance between the star will surly have the technology to hid from us if they want to.

If they do want to communicate with us, they will, and in a clear way. An advance race with starships will not resort to Crop Circles to communicate with us.

There is a third possibility- they may not care whether we see them or not. If this was the case, we would have better evidence of their visits.

I have yet to see a UFO picture I couldn’t fake. In fact, I have faked some just to see if I could.