Gracelin Baskaran, the director of the Critical Minerals Security Program at the Center for Strategic and International Studies in Washington, is a leading expert on the elements buried in the Earth’s crust and how they affect the global economy. The International Energy Agency estimates that China controls 60 percent of the global mining and 90 percent of the refining of rare earths, which are vital components in goods such as semiconductors, engines, and missiles. We spoke shortly after t