* The Martian environment: The planet itself is hostile, with a thin atmosphere, extreme temperature fluctuations, and deadly dust storms. This makes survival difficult and puts a constant strain on the colonists' resources.
* The Martian civilization: The Exiles, who are descendants of early Martian colonists, have been cut off from Earth and forced to live in fear of the hostile native Martians, who are described as "the old ones" and possess advanced technology.
* Their own actions: The Exiles have become increasingly isolated and suspicious of each other, leading to conflict and distrust within their own community. They also struggle with their own internal conflicts, such as the desire for progress and the fear of losing their identity.
It's important to note that the story does not explicitly blame any single entity for the devastation. Instead, it presents a complex picture of a society struggling to survive in a harsh and alien environment. The "old ones" are presented as a constant threat, but the Exiles' own actions also play a significant role in their suffering.