After being discharged from the Navy in 1934, Heinlein moved to Los Angeles, where he was eventually elected to the West Hollywood Democratic Club’s board of directors and helped organize Upton Sinclair’s “End Poverty in California” (EPIC) campaign for California governor. The socialist Sinclair ran on a platform of using government credit to buy failed factories and farms and redistribute them to the unemployed. Heinlein, whose family farming business was ultimately displaced by IH, found Sinclair’s critique of monopoly capitalism appealing, and he tended to idolize individual entrepreneurs (like the boy inventors in his early reading) and small farmers. 

In 1935, Sinclair assigned Heinlein the task of investigating strikes in the Imperial Valley, where agribusiness monopolies reigned with a heavy hand. Heinlein was "appalled and outraged” by the vigilante violence directed at workers that he witnessed during his fact-finding trip. On his return to Los Angeles Heinlein made a presentation before the West Hollywood Democratic club in which he screened a newsreel about the strike and concluded that the “Constitutional rights of workers in Imperial Valley have been abrogated by some of the citizens and elected officials in [an] amazing display of vigilante activities.” 

Heinlein’s fiction, however, represents a contradictory combination of anti—agribusiness and anti—farm worker perspectives, perhaps best represented in his novel Farmer in the Sky (1950). It is set sometime after 1998, when food shortages resulting from overpopulation compel its protagonist, a California teenager named Bill Lermer, to contract with the “Colonial Commission” and emigrate with his family to a farming colony on Ganymede, one of Jupiter’s moons. The immigrants had been promised free land for farming but on arrival it is revealed that their housing is inadequate and that the massive tractors and rock crushers required to terraform the planet are in short supply. As a result, “it might be two or three years before any particular immigrant got a chance to process his first acre of ground.” If they are to eat in the meantime, the immigrants are forced to indenture themselves to earlier immigrants with already established lunar farms. 

After their period of indenture, Bill and his father borrow the necessary machinery and terraform a five-acre plot of land, build a rock farmhouse, and begin growing food. Bill subsequently joins a “pioneer party” of other young men to scout out new farmland. Along with another boy he discovers a mysterious crystal cave containing "a sort of tractor thing," an elaborate mechanical vehicle resembling a giant metal centipede that the boys surmise was left behind by aliens. 

They ride the strange tractor out of the crystal cave and back to the safety of camp and finally to their new “homesteads,” where Bill expresses his identification with the machine’s alien makers: “they controlled their environment. They weren’t animals, pushed around and forced to accept what nature handed them; they took nature and bent it to their will. I guess they were men.” This encounter with alien yet familiar masculine farm technology finally seems to prompt his decision to remain on Ganymede, where it was “new, hard, and clean,” and become a “Farmer in the Sky.”   

The novel projects a critical alternative-future rejoinder to its actually existing present, where agriculture was dominated by corporate interests that had largely squeezed out family farms. At the same time, however, Farmer in the Sky poses the speculative question: What if an exemplary white US American boy was forced to become a lowly farm worker? Anticipating a number of similar science fiction narratives, the novel constitutes a sort of race and class thought experiment that subjects its white male protagonist to conditions experienced by racialized migrant farm workers: limited access to work and food prompts dangerous, long-distance travel; on arrival the migrant discovers that housing and employment conditions have been dramatically misrepresented; and the migrant is forced by circumstances to accept difficult and debilitating “stoop labor,” a form of agricultural work that growers argued Mexicans were naturally well suited for, and that reproduced farm worker abjection.

The novel’s striking cover by Clifford Geary, who illustrated Heinlein’s juvenile space fictions, centers stoop labor. Resembling period photos of farm workers using short-handled hoes, the cover depicts a Ganymede farm with a pitchfork-holding farmhand standing up and resting in the foreground while in the receding distance a tiny stooped over figure works amid the rows of crops. Rather than becoming bent and broken by stoop labor, or beaten down like the Mexican and Filipino farm workers Heinlein encountered in the Imperial Valley, Bill ultimately rises, and becomes a successful settler. The white space immigrant is not limited to materially and symbolically diminishing forms of racialized work such as  “sharecropping” and stoop labor—he is a heroic “homesteader,” “pioneer,” or “settler” colonial who stands up on his own two feet and bends the world to his will. From this perspective the futuristic white farm worker serves to denigrate actually existing farm workers who by implication are more “like animals, pushed around and forced to accept what nature handed them.” Finally, technology serves as a key marker of the difference: whereas farm workers of color are supposedly dwarfed and dominated by industrial farm machinery, the white farm boy masters it. The 1975 reissue of the novel includes cover art of the white farm boy in space that anticipates Luke Skywalker.

The agribusiness context informing Farmer in the Sky ripples throughout Heinlein's other narratives of space travel. While not expressly about agriculture, for example, his novel Starship Troopers about a war between earthlings and alien arachnoids bears the traces of farm-worker contexts like those Heinlein encountered in the Imperial Valley. The book's protagonist, Johnny Rico, is a Filipino immigrant and enlisted man whose race and low status recall period representations of farm workers. The film adaptation captures the novel's idealization of fascism in ways that recall "farm fascism."  

Heinlein's two screenplays about travel to the moon also recall the migrant worker thought experiment of Farmer in the Sky. In Destination Moon (1950), the future of the world depends upon the willingness of benevolent corporate CEOs to sponsor a lunar voyage in advance of the Soviets. The blast off to the moon, moreover, suggests a science fiction rewriting of the difficult journey of migrant workers. Four men (a rocket scientist, a retired general, an industrialist, and a radio technician) dressed in denim-colored jumpsuits that resemble work uniforms more than space suits say goodbye to their loved ones and board a rocket with the Spanish-language name Luna in the New Mexican desert. As the rocket blasts off, the force of their movement through space is visible on the astronaut's strained faces and strapped down bodies, only to be replaced by space sickness once they leave Earth's gravity. The focus is on the visceral effects of displacement in time and space, suggesting a fantastic reimagining of migrant worker trajectories. 

The moon launch in Heinlein's Project Moonbase supports a similar interpretation. In the future world of 1970, a group of astronauts weather the force of displacement in time and space as they travel to the moon on a rocket called Mexico.