But they are observing us from so far away, that they are seeing our planet several million years in the past.
As soon as they detect human life they will come and attack. But by the time they detect humans and make the long trip in their mega monster death spaceships that blow up our biggest and most iconic metropolitan areas....we will be several million years advanced and will be well prepared for their arrival.
And the reason we will be well prepared is because President Trump started a space force.