The United States is in a titanic struggle with the People's Republic of China for the dominance of space.
Although the Americans have been to the moon and sent multiple, advanced probes to the surface of Mars, since the end of the Cold War, U.S. space policy has languished in neutral. Due to this, new competitors, namely China, have arisen to challenge the dominance of the Americans in the ultimate strategic high ground of space.
China has grand ambitions for space. Not only does China plan on beating the Americans to the Martian surface by the end of the decade, but Beijing wants control of the vital orbits around the Earth. By controlling these orbits, China's military would enjoy significant advantages over the American military. Beyond that, China plans on strip-mining the moon for valuable resources.