In the quote from Sinclair Lewis's "It Can't Happen Here," the author reflects on the fragility of civilization and the thin veneer of progress that separates society from chaos. He warns that an overwhelming assault, symbolized by shells and gas bombs, could easily dismantle the achievements of humanity, including knowledge, culture, and infrastructure. This scenario illustrates a profound fear that the advancements and civility humanity has built could be eradicated with a single catastrophe.

Lewis suggests that if such destruction were to occur, future generations might regress to primitive lifestyles, disconnected from the intellectual and cultural heritage that defines civilization. His bleak vision underscores the vulnerability of society to destruction, emphasizing the importance of preserving knowledge and promoting tolerance. The underlying message serves as a cautionary tale about the consequences of neglecting the foundations of learning and civility.