In the 1970s Marty Cooper, a former Navy submarine officer, engineer and executive at Motorola, maker of two-way radios, fought against archrival AT&T by proposing a network of transmitters that made possible the explosion in cellphones. Correspondent David Pogue talks with the visionary Cooper, now 92, about the world's first public cellphone call, on April 3, 1973, and about his unbridled optimism for the future. Air Date: Aug 22, 2021