Final answer:
The highways between Oklahoma and California during the era of westward migration resembled a conveyer belt, and are part of a larger narrative of American progress symbolized by the continuously developing highway system and westward expansion.
Step-by-step explanation:
Writers of the era observed that the highways between Oklahoma and California resembled a conveyer belt, with a continuous string of cars heading west. This mass movement was part of a larger historical narrative of westward expansion, symbolized by artworks such as "American Progress," where the personified America heads west carrying a school book and the telegraph.
The development of highway systems and the concept of Manifest Destiny fueled the suburbanization and navigation of vast distances, as evidenced by Interstate 405 in Los Angeles and other highways that facilitated movement and development.
With the advent of the automobile, increased road construction was inevitable, leading to an expansive network of local, state, and eventually, an interstate highway system. These highways were essential in transforming American society and economy, enabling rapid westward migration and the growth of suburbs. Landmarks such as the Cadillac Ranch on Interstate 40/Route 66 serve as a cultural commentary and a reminder of the transient nature of the American journey.
The evolution of American thoroughfares, from barely passable trails to multi-lane highways like the one near Sepulveda Pass, has influenced cultural, technological, and demographic shifts in the United States—a history deeply intertwined with the expansive, straight roads that cut across the country.