Green technologies such as electric cars, wind turbines, solar panels and fluorescent light bulbs rely on rare-earth metals. The military depends on rare earths for guided missile systems, satellites and unmanned drones. NASA's spacecraft carry powerful rare earth magnets to Mars and outer space. The magnets also miniaturized iPads, computers and high-tech headphones.
China controls 95 percent of the world's rare-earth supply. The key to this monopoly isn't an abundance of rare-earth deposits, but its expertise in processing ore into oxides and pure metal. The ore tends to carry uranium and thorium, the most radioactive element on the planet, and extracting the metal is typically a long, multistage process involving toxic chemicals.