"Catastrophe," "holocaust," "apocalypse" and "terror" are all used interchangeably by scholars discussing similar subject matter. I've read the discourse of terror as a reworking of the discourse of the Cold War and the devastation of the population.

In Apocalypse, Ideology, America: Science Fiction and the Myth of the Post-Apocalyptic Everyday in Rhizomes Matthew Wolf-Meyer says:

The post-apocalyptic narrative has been seen as one of three possible readings: 1.) The re-advancement of technology, thereby allowing the reader to perceive the inevitable triumph of technology in a more primitive society than his or her own, 2.) A warning against war, which is simply political in that it attempts to defuse militaristic leanings within the culture that has influenced the author to produce the novel, or 3.) The neo-Luddite reduction of modern society (or possibly near-future society) to a simpler version, sometimes also allowing the author to entertain "inevitable" historical cycles if the narrative spans the chronological development of a culture of post-apocalyptic survivors, as is the case with Miller's A Canticle for Leibowitz.

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