Out of historical interest, I recently purchased a copy of Seduction of the Innocent by psychiatrist Fredric Wertham M.D. At approximately 400 pages, the 1954 book led to the development of the Comics Code that year and had a lasting influence on public opinion about comic books.
Amid his sweeping generalizations, Wertham's treatise issued numerous concerns against comic books. He warned that even children who appear to enjoy only animal comics like Donald Duck might secretly read crime comics (including Westerns and superheroes), which Wertham found particularly dangerous.
According to Wertham, the prevalent violence within crime comics directly contributed to juvenile delinquency and disturbed thinking. As an example, Wertham told of a nine-year-old boy who insisted his favorite comic book was called Human Torture rather than Human Torch.
In discussing superheroes, Wertham leveled most of his attacks against a handful of DC characters. Many comic book fans today are well aware of Wertham's homophobic inferences about Wonder Woman, and the partnership between Batman & Robin. Similarly, Wertham criticized the salaciousness of "love comics" as a genre.
As for Superboy/Superman, Wertham argued that the character's unrealistic powers misled children about the laws of science and overshadowed historical figures deserving of true admiration. To Wertham, Superman embodied the dangerous ideal of a super-race. Wertham found fault with other comics, particularly those with Jungle settings, for for their racist depictions of native peoples.
Discrediting the literary merit of comics, Wertham noted their frequent reliance on words like BLAM and KAPOW. Further, their vivid illustrations made comic-book depictions of horror far more pernicious to Wertham than the most unsettling fairy tales.
Wertham felt that comic book adaptions of classic literature, such as Robert Louis Stephenson's Dr. Jekyll & Mr. Hyde, corrupted the source material and failed to motivate children to seek out the original text. In contrast to comic books, Wertham saw educational promise in film and children's television, media that are also intrinsically visual.
Wertham's concern about the content of comic books extended to the advertisements within. He deplored ads for (largely ineffective) health products that capitalized on the insecurities of girls and boys. Wertham also condemned ads for B.B. guns and knives, regarding these weapons as inappropriate for children.