He's back. A recent TV program has reintroduced Superman-as a teenager. In his latest incarnation, the Man of Steel struggles as much with his teen emotions as against evil, Superman has been reconstructed to fit the times, for pop culture demands super characters to suit current tastes. More and more of the superheroes that populated the comic books of earlier generations have muscled their way into the twenty-first century, still saving the day after all those years-but not without their share of inner turmoil and outer struggle. 　It seems that fans don't really want their superheroes to be too super. Take the X-Men, introduced during the Cold War when America's optimism had been dampened. Admittedly, these characters were introspective and psychologically complex to begin with, being driven more by guilt than the desire for revenge and honor of earlier characters like Superman and Wonder Woman. 　Today's X-Men, though, while capable of every eye-popping feat Hollywood can dream up, are even more clearly flawed, fitting naturally into today's world, where the lines dividing the good guys and bad guys have become blurred, and the good guy so often don't win.   So why not just create completely new characters instead of reconstructing the old? There are two reasons. First, superheroes aren't created overnight. Superhero characters have to exist for several years or decades to achieve the status of myth, and nothing serves a superhero like myth status. And secondly, today's comic books just aren't creating memorable new characters. Their golden age has expired. Kids have turned to video games, but video-game superheroes are character duds, They may do super deeds, but they are devoid of depth.