Ada: So beginning in nineteen forty-two, the United States built something unprecedented - a secret industrial system stretched across the whole country to make an atomic bomb.
Theo: How do you even hide something that big?
Ada: You break it into pieces most workers never fully understood. Uranium was processed at Oak Ridge in Tennessee. Plutonium was produced at Hanford in Washington State. And the bomb itself was designed at Los Alamos, up in the New Mexico mountains.
Theo: Three sites, thousands of miles apart, and most people didn't know what they were building?
Ada: Most didn't. Behind fences and security checks worked physicists, soldiers, machinists, technicians. The scientific director at Los Alamos was J. Robert Oppenheimer.
Theo: And already, somewhere in this, someone's thinking about targets?
Ada: Yes, and I want to be precise here. Hiroshima was chosen as an important military center - and, notably, as a target without known American prisoners of war nearby. Not simply picked as an anonymous civilian city.
Theo: That's a distinction worth sitting with. Cold, deliberate reasoning.
Ada: It was. But none of it counted until they knew the thing would actually explode.
Theo: Which brings us to a desert before dawn, and a fireball nobody was sure would come.