China cannot be compared to the US just yet. China is way too unstable. Over half of their population is still living under poverty, and they treat other non Chinese population living in China badly. There are way too many problems which China has to overcome. If it does not do that, they can say good bye to the 21st century being the century of China.
Every country goes through a cycle. I think the average length of peak is 80 ~ 120 years? The US was not even considered a super power before WW 1. Unlike other countries with richer histories, a country formed by immigrants need something to pull their citizens together. I think I read an article a long time ago saying how the US does this with their flag. Unlike the Western countries, the Eastern countries have one major population group in their countries and people look alike as well giving them a sense of unity. This generally leads to racism and with some government propaganda, people become pretty patriotic. They also use history as a tool of propaganda as well.
