From where we sat with our backs against a white-speckled granite rock on the top of Mather Pass at 12,100 feet in the southern Sierra, the view could have fit with any good post-apocalyptic science fiction novel: bare jumbled rock spreading away to the horizon south and north, rimmed by the next column of stark dry peaks, sparse alpine plants clinging to fragile rootholds, scattered tarns reflecting the striking blue sky above, and not another soul in sight for miles. It would be easy to imagine that something big went “BOOM!” here and the lifeless land had not yet healed its scars.