In The Grapes of Wrath, John Steinbeck suggests that people like the Joads are affected by economic changes which are not of their making but that this family is still responsible for many of its own problems after that basic fact. One reason why it is evident that Steinbeck is dealing with larger economic forces is found in the interchapters in which Steinbeck does not directly advance the story of the Joad family but instead offers increased depth and broader significance to the novel by giving background, discussing issues of the time, and offering an external perspective on the Depression. Here, Steinbeck can expand on his view of a class struggle in American society as the immigrants who have nothing move toward the landowners who have much:
The western land, nervous under the beginning change. The Western States, nervous as horses before a thunder storm. The great owners, nervous, sensing a change, knowing nothing of the nature of the change. . . The causes lie deep and simple--the causes are a hunger in a stomach, multiplied a million times. . . (192).
The world of the Joads is a world that exists on wheels. These are people who lived by the land but who have now been removed from that land, and this is a wrenching experience for all of them: "Every night a world created, complete with furniture--friends made and enemies established; a world complete with braggarts and with cowards, with quiet men, with humble men, with kindly men" (250). This is a world that serves as a microcosm of the rest of America, a world that is living more speedily, with friends made and lost in a single night, with households created and dismantled in one day. This is a microcosm showing how Americans developed their nation and how they improved every aspect of their lives because they had no choice: "The families moved westward, and the technique of building the worlds improved so that the people could be safe in their worlds; and the...