Architect John Portman was famous for building modern skyscrapers with soaring atriums, including Detroit's Renaissance Center and Atlanta's Peachtree Center. The structures were often built as part of urban renewal efforts, but many critics say they did little to draw people to struggling downtowns. Portman died Friday at age 93.
This week's terror attack in Manhattan prompts a question: Can a city do anything to stop a truck attack? NPR's Mary Louise Kelly speaks with architect Thomas Vonier about how we can better design big cities to make it harder for terrorists to harm people.