Rare earths are needed for everything from consumer electronics to electric vehicles, wind turbines and fighter jets – and China controls the supply chain. In the second of a four-part series, we look at how China gradually took a commanding role in the rare earth industry, and how the US is now working to strengthen its sources and production.Nearly a half-century removed from being the world’s dominant supplier of rare earth elements, California’s Mountain Pass mine is once again being tasked...