The celebration of sex in Atlas Shrugged was fairly controversial in straight-laced 1950s America. Sex is an expression of the strikers' value system, which prizes individual happiness and the uniting of the mind and body. Denying individual physical impulses is as bad as denying individual happiness.
Other characters take a very negative view of sex, treating it as shameful or tawdry. People who condemn sex are themselves condemned here, largely by Francisco and Dagny, who each give speeches defending sexuality.
This isn't to say that Galt and his strikers are advocating a sexual free-for-all. They actually promote highly discriminating sex, between people who love and/or admire each other. In other words, the mental and the physical should reflect each other. But Galt and his followers do seem to largely ignore or dismiss conventions like marriage and celibacy, which puts them at odds with society at large. Sex is not a sin in Galt's value system.
Questions About Sex
How do people like Galt, Dagny, and Francisco connect love and sex?
Why is Hank so obsessed with finding out who Dagny's first lover was? Is there any thematic significance to this obsession?
Are there any similarities between Hank's and Lillian's views on sex?
Men in the novel seem to either view Dagny as a sexual object – a dirty mistress – or a sort of pure, untouched goddess. Are there any connections between these two different views? How are these views significant in terms of the book's themes?
Chew on This
The fact that both Eddie and Hank treat Dagny like an untouchable queen reflects broader social views about sex and gender.
Sex in and of itself is not viewed positively in this book, only sex as an expression of love.