Under Joe Biden's direction, the US Trade Representative (USTR) launched a probe Monday into China's plans to globally dominate markets for legacy chips—alleging that China's unfair trade practices threaten US national security and could thwart US efforts to build up a domestic semiconductor supply chain. Unlike the most advanced chips used to power artificial intelligence that are currently in short supply, these legacy chips rely on older manufacturing processes and are more ubiquitous in mass-market products.