What significant change in transportation occurred after World War I?

The widespread use of automobiles after World War I represented a major transformation in transportation. The post-war period saw significant advancements in automobile manufacturing, which were primarily driven by the mass production techniques perfected during the war. This made cars more affordable and accessible to the general population. The rise of automobile ownership not only changed personal mobility but also influenced urban planning, as cities began to adapt to accommodate roadways, parking, and the suburban lifestyle that automobile use encouraged.

In contrast, while railroads and public transportation systems saw developments during this time, they did not experience the same level of revolutionary change that the automobile industry did. The advent of airplanes also made strides post-war, but it was not until later that air travel became common for the general public. The true defining aspect of transportation changes after World War I was the dramatic increase in automobile usage, reshaping society and economies across the United States and beyond.