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The Weight of What They Built: Conscience, Creation & the Bomb
Audio is available on Spreaker — see link below.
From Einstein's 1939 letter to the ruins of Hiroshima, the Manhattan Project reshaped civilisation — and left 130,000 people asking whether they'd made the right choice. This chapter traces the full arc: Fermi's chain reaction, Oppenheimer's Los Alamos, and the moral reckoning that followed.
Audio is available on Spreaker — see link below.
What the Manhattan Project left behind wasn't just two destroyed cities. It was a question that every scientist who touched the project had to answer for themselves, privately, for the rest of their lives.
The beginning is August nineteen thirty-nine. Albert Einstein signs a letter to President Franklin Roosevelt.
The scale of what Groves assembled is still hard to fully grasp. Across thirty sites in the United States and Canada, roughly one hundred thirty thousand people worked on the Manhattan Project at its peak.
Before Los Alamos could build anything, someone had to prove the underlying science actually worked. That proof came from Enrico Fermi.
Here's where the physics became genuinely brutal. The scientists knew they needed fissile material.
To answer that question, they built a test device called the Gadget. On July sixteenth, nineteen forty-five, at five twenty-nine in the morning, the Gadget detonated at a site called Trinity, thirty-five miles from Socorro, New Mexico.
Leo Szilard had been thinking about this moment for months. He'd circulated a petition in July nineteen forty-five, after Trinity but before the bombs were used.
On August sixth, nineteen forty-five, the uranium bomb called Little Boy was dropped on Hiroshima. Approximately one hundred thousand people died on that day or shortly after.
The secrecy the Manhattan Project relied on was also, in part, an illusion. Klaus Fuchs was a German-born British physicist working at Los Alamos.
Einstein spent his last years campaigning for nuclear disarmament. He called the Roosevelt letter, the one Szilard brought to him in nineteen thirty-nine, the one great mistake in his life.
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