Ok, so basically, these aliens are super powerful and super intelligent, and they have done things for us before. They even have walked among us before. But we don't know about them, and for the next disaster, they will do their very best to save us but without revealing themselves.
So what that means is these aliens are God?
And if they think they can reveal themselves in such a way that we won't be frightened, they obviously haven't met some of the old people I know.