An Orlando Sentinel article has Ramsey Campbell reminiscing about how the government almost took down Analog magazine in 1944 (when it was still called Astounding Science Fiction) because of a short story it published (“Deadline” by Cleve Cartmill) that gave a few too many details about atomic bombs.
When intelligence agents came calling, Cartmill blamed it all on Campbell, who had provided him with all the technical details he used in the story. Campbell, who had studied physics at MIT in the early 1930s, told investigators he learned it all in college. However, he had flunked out his sophomore year, according to a recent article by Robert Silverberg. But Campbell liked to keep up on the latest science journals as part of his job, it seems. The military wanted the magazine shut down, but cooler heads prevailed.
The Office of Censorship ultimately concluded the details in the story could have been “produced by any person with a smattering of science plus a fertile imagination,” according to an article on the incident on the Popular Science Web site.