Had I been wrong, this would still have been the honorable thing to do. I am very glad, however, to find out that I was right. - David Brin

Apocalypses, apparently, are subject to fashion like everything else. What terrifies one generation can seem obsolete and trivial to the next. Take our modern attitude toward war. Most anthropologists now think this activity was based originally on theft and rape—perhaps rewarding enterprises for some caveman or Viking, but no longer either sexy or profitable in the context of nuclear holocaust! Today, we look back on large-scale warfare as an essentially silly enterprise.

The lesson they took home with them was simple; it takes a full belly before a man or woman gives a tinker’s damn about anything as large as a planet.

Other generations perceived a plethora of swords hanging over their heads. But generally what they feared were shadows, for neither they nor their gods could actually end the world. Fate might reap an individual, a family, or even a whole nation, but not the entire world. Not then.
We, in the mid-twenty-first century, are the first to look up at a sword we ourselves forged, and know, with absolute certainty, it is real...