Traditions are imploding and exploding everywhere - everything is coming together, for better or worse, and we can no longer pretend we're all living in different worlds because we're on different continents.
Racism is taught in our society, it is not automatic. It is learned behavior toward persons with dissimilar physical characteristics.
I grew up in the '80s where there's a lot of these kind of post-apocalyptic, post-comet, post-whatever it was, so that always captured my imagination a lot as a little kid, that idea of getting access to secret places and being able to roam around where you're not supposed to.