The American company Nvidia has created one of the world’s most sought-after inventions: a computer chip that powers artificial intelligence. Amid concerns that the technology could help China modernize its military, however, the United States has tried to control the export of the chips. Ana Swanson, who covers trade and international economics for The New York Times, discusses her investigation into the escalating war over the technology. Guest: Ana Swanson, who covers trade and international economics for The New York Times.