"Red Planet", for example, portrays some subversive themes, including a revolution in which young students are involved; his editor demanded substantial changes in this book's discussion of topics such as the use of weapons by children and the misidentified sex of the Martian character.Heinlein was always aware of the editorial limitations put in place by the editors of his novels and stories, and while he observed those restrictions on the surface, was often successful in introducing ideas not often seen in other authors' juvenile SF.