Coming from the Congo, I knew where the essential ingredient for the atomic bombs was mined, even if everyone else seemed to ignore it.

Papà, my dad, told me a story long ago about the uranium that powered the first nuclear bombs. The ones dropped on Hiroshima and Nagasaki; the bombs you saw being built in this summer’s dramatic film, Oppenheimer. Papà, you see, was born in the Belgian Congo.

Earlier this summer, I was invited to a screening of the blockbuster. The film’s director, Christopher Nolan, was there too. In a recurring scene, meant to symbolize the inching along of the scientists’ efforts, Oppenheimer fills an empty glass bowl with marbles—first one at a time, then in handfuls. The marbles represent the amount of uranium that has been successfully mined and refined to power the nuclear reaction. The outcome of World War II, and the future of humanity, hinges on who can create that monster first—the Axis or the Allies. The closer we get to the bomb’s completion, the more marbles go into the bowl. But there’s no mention in the film of where two-thirds of that uranium came from: a mine 24 stories deep, now in Congo’s Katanga, a mineral-rich area in the southeast.

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