What are the motifs in The Cage by Ruth Minsky Sender?

The power of propaganda is a recurring idea in the story. While the atrocities of the Nazis were an important part of the story, an even greater problem for Riva was how much of the Nazi propaganda was true. She noted that the workers at her shop were all called outside one day where they were urged to volunteer to be moved to a different location. There were promises of a better life for those who volunteered and Riva, along with everyone else, was faced with a life-and-death decision. Riva's family was barely subsisting on the food ration and Riva's health was quickly deteriorating.