I don't think we can compare the U.S. to China. China has been around for thousands of years while the U.S. is the newest country compared to most countries, people didn't really know about this piece of land until Christopher Columbus.
However I don't think democracy is working either because some people don't make well informed decision when voting for the nation's leaders. High school graduation rates in the U.S. is low, some people who didn't get education still vote and they pick people who may not be qualify. We got people voting base on looks, and people can't see that lots of candidates try to market themselves to a targeted group of people by addressing one or two issue that group is concern about.