One very significant challenge was the challenge of globalization. This helped make the US a "restless giant" because it made Americans feel that they were losing their economic dominance in the world. During this time, the US economy was facing increased competition for foreign countries. The main worry for America during much of this time was competition from Japan. The US was still a giant in that it was a superpower with the biggest economy in the world. But it was becoming restless because of the fact that it was becoming less dominant and the fact that it was losing manufacturing jobs to other countries.