China's vast territory gives it enough rivers, arable land, and mineral deposits to supply itself without imports, much like the US or Russia. In a war, it wouldn't face resource shortages the way smaller nations would.
Chapters
China is a continent-sized country. So anytime you hear that the United States is uniquely blessed in natural resources, which it is to a great extent, consider that China is likely America's equal. It has great rivers, it has ample arable land, and it has vast deserts and mountains where no one objects to very intensive mining or resource exploitation. It makes less sense of thinking a country like Russia or America or Canada being resource constrained. The more land you have, the likelier it is that you can find and exploit natural resources. So the United States can likely find anything it needs in its territory in a situation of war. But the same is also true of China. China is not a high population density, medium-sized industrial country dependent on international trade for its resources. It actually could develop most resources domestically.