If we are being monitored by aliens, then I suspect they would be aware that knowledge of them, at this moment, would probably trigger a planet-wide civil war. We are still too intolerant and afraid, many countries would see the existence of extra-terrestrial life as a threat to every tenement they have founded their country on, still too many theocracies and theocratic democracies.
That said, I will stress that, in this case, I don't see religion being so much the problem, as the fact of religions' ties to government. I wouldn't be the least bit surprised if Aliens, if they came, had religions of their own, for all its faults, religion is a sign of a mentally advancing species.
