When extraterrestrial life reveals itself to us, it will probably have parallels to when the Spanish discovered the new world. That didn’t turn out so well for the native population.
I think they, whomever they are, have been here for eons but an official announcement from our "rulers" is not so forthcoming. Indeed, the population might very well freak out at the prospect of our own mortality because we have a species wide spiritual malady. JMHO