To discuss the national security risks of Nvidia's CEO having an affair with a possible foreign intelligence agent, Amna Nawaz spoke with Christopher Johnson. He spent 20 years in the U.S. intelligence community focusing on China. He now runs his own consulting firm, China Strategies Group. Geoff Bennett: Well, for its part, the broader market rallied today, but Nvidia shares took a hit, closing down more than 4 percent. And the economic stakes extend well beyond Nvidia itself.