Superman needs to ditch his clean-cut image for good, and return to his roots as a ruthless champion of the oppressed. Superman has been a pop culture fixture for 87 years. In that time, he has undergone significant changes, both in power levels and in his mission. The story of Superman's gradual shift in priorities reflects American history. Today, Superman is one of DC’s marquee characters, and part of its “Trinity,” alongside Batman and Wonder Woman. Superman’s colleagues view him as highly moral. Superman is averse to using lethal force on anyone, and his code of ethics has earned him...