by Kevin Merida and Richard Leiby

About the authors: Kevin Merida and Richard Leiby are staff writers for the Washington Post.

In what used to be the dark corners of our culture, there is a prime-time cartoon with a neo-Nazi character, comics that traffic in bestiality, movies that leave teenagers gutted like game, fashion designers who peddle black leather masks and doomsday visions.

It’s all in the open now, mass-produced, widely available. Even celebrated. On countless PCs, killing is a sport. And there’s Marilyn Manson, a popular singer who named himself after a mass murderer and proclaims he is the Antichrist.

Film, television, music, dress, technology, games: They’ve become one giant playground filled with accessible evil, darker than ever before.

After any tragedy involving children, the commentators strive to...