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Why, they could take their revenge, couldn't they.
This whole thing is stories built upon stories built upon stories. It's stories all the way down till you reach The World Set Free by British propaganda writer H.G. Wells, published in 1913–14 as part of the British war propaganda preparations against Germany. I don't recommend the book, it's psychologically dull and constructed, but that's where Leo Szilárd picked up the idea of an “atomic superbomb” in 1932 when reading the novel, which led to the Einstein letter in 1939. Well, according to the story anyway.