For every instance of bloodshed in entertainment, there has been a naysayer around to criticize it. While this high sensitivity to media violence may seem like an entirely modern invention, this phenomenon has been around for ages. While "ultra-realistic" violent video games and rap music are recent targets, moral panic against controversial arts and entertainment is well-documented. Books, films, and rock-and-roll have all been blamed for corruption of the youth, but one major movement in the past that sticks out is the one against comic books in the 1940s.
The name "Frederic Wertham" is one still infamous to comic book fans. A seemingly reputable psychologist, Wertham was able to change the entire comic industry for decades with his book Seduction of the Innocent. By linking comic books to juvenile delinquency, communism, homosexuality, and other unsavory activities, the book led to massive comic book burnings and the creation of the "Comics Code Authority", which effectively killed the then-popular genre of horror comics. While Wertham's research was flawed (he studied delinquents, but did not contrast them with average comic readers) and his demographics were misjudged (horror comics were primarilly read by soldiers to kill time during the war, not by children), his book forced the entire industry to shift away from the violent tone of the comic book "Golden Age" to the more wholesome, family friendly, and explicitly anti-communist "Silver Age".
And, of course, one cannot bring up the impact of media violence on society without mentioning "Doom", the video game that supposedly inspired the tragic Columbine massacre. Since the perpetrators were both active players of the game (one of them even "modded" the game by coding his own custom levels), the media instantly sought to link these senseless killings to the popular shooting game. Of course, this fails to take into account that one of the killers admitted to using "Doom" to re-enact scenarios that he had already imagined himself, and used it more as an outlet for his "creativity" as opposed to a source of inspiration. And, like all reports blaming media violence for society's ills, this theory fails to take into account the clear mental and emotional issues that the two boys had, which ultimately led to the unfortunate incident.
Blaming the media is nothing new. But nowadays, comic books seem harmless. Batman, the alleged homosexual pedophile and menace to society, is now an iconic fictional character, and the massive panic over crime and horror comics seems silly now. Comics were read by the vast majority of children during the 1940s who grew up just fine. Theories like Dr. Wertham's were ridiculous then and are ridiculous now.