China just added MP Materials and USA Rare Earth to its export control list, cutting off dual-use exports to both companies. MP Materials runs the only active rare earth mine in the US and is Pentagon-backed. The move is retaliation for Washington adding Alibaba, Baidu, BYD and NIO to its list of Chinese firms linked to the military. Analysts are calling it largely symbolic since these US defense companies weren't doing much business in China anyway. But symbolic or not, China just put its hand on the one supply chain the US can least afford to have disrupted.(Lark Davis)