With an interest in cosmology, suppose a federation of planets of different intelligent species who all got on well together were to contact us and ask us to join. Would we accept, would we be accepted when we cannot seem to get on with ourselves as an intelligent species. At least the XMarkers get on well together.
It seems there is still a tribal mentality afoot no matter what form the tribe takes.
I consider myself not a member of any tribe.

Chris.