Often, when science fiction novels get rejected, there's some political shenanigans at work. Take case of Ben Bova, whose first novel correctly predicted that the Soviet Union would beat the United States into space — and publishers wouldn't handle it.
Writing in his regular column for the Naples Daily News, Bova recounts how he decided, in 1949, to write a novel about the first person on the Moon. Because the Soviet Union had just exploded its first atomic bomb, years before most analysts had expected the Soviets to master the technology, Bova decided to write a novel in which the U.S.S.R. gets into space before the U.S., catching the Americans by surprise. The U.S. launches a desperate program to get to the Moon before the Soviets do. As Bova says:
A crazy plot. Nobody believed it. Nobody wanted to buy my novel.
He sent it to every publisher in New York, and they all turned it down. Finally, he sent it to a young adult publisher in Philadelphia, who agreed to meet with him:
The editor was a kindly gentleman who told me, near as I can remember his words:
"Look, kid. This novel of yours isn't as bad as some of the things we do publish. But you've got this weird plot: the Russians going into space before we do. Nobody's going to believe that."
So much for literary quality.
"Besides," the editor went on, "there's this guy in Washington, Sen. Joseph McCarthy, who's searching for communists all over the country. If we published a novel that even hinted that the Russians were smarter than we are, he'd make our lives miserable."
The editor advised Bova to write another novel — one set so far in the future that "nobody can connect it with today's politics." And so a career was born. [Naples Daily News]