U.S. tariffs' delayed effects on America

From the BBC World Service: The past 12 months have brought lots of turbulence to global economies, from fast-changing U.S. tariff policies to the rapid acceleration of artificial intelligence. As we ring in the new year, what might 2026 hold? Plus, billions of dollars have poured into AI development, but there are increasing concerns about a market bubble. What are the chances it will burst?