As you ascend higher into the sky, most of the natural and man made delineations of the earth start to merge into one another.
That is one side of truth—that all the labels we've created for ourselves and for others, from a certain perspective, aren't real—they fade away.
The other side is that they are, of course, real. When the plane lands, all the detail comes back into focus.
It's a subtle indicator of the non-attachment concept, i.e., not getting hooked on either this or that, but seeing that it is this and that happening at the same time.
In ourselves and in others.