When eckels returns from the world of dinosaurs what is different about the present?

When Eckels returns from the world of dinosaurs in "A Sound of Thunder," he discovers that the present has drastically changed. A seemingly minor change in the past has led to significant alterations in the present, including the emergence of a totalitarian regime and the death of a key historical figure. The atmosphere is oppressive, and even the language has shifted, reflecting the far-reaching consequences of his actions in the past. This illustrates the theme of how small actions can have profound effects on the future.