At The Atlantic today, Noah Berlatsky of the Hooded Utilitarian argues that Superman has not wandered far from his historical roots in racist fascism, which is even more reason to be concerned that anti-gay writer Orson Scott Card is writing Adventures of Superman. I won't comment on his spurious links between the Ku Klux Klan and Superman, much less his statement that "even at this late date, it's just not that hard to look at Superman and see the outlines of the KKK." (For a better look at Superman and the Klan, see this piece by Carol Borden at The Cultural Gutter, and for commentary on the links between fascism, Nietzsche, and Superman, see the chapters in part three of Superman and Philosophy.)
Berlatsky's main substantive points seem to be that 1) Superman is a "violent vigilante" and 2) violent vigilantism invariably and inevitably becomes directed towards the powerless in society. The first point is merely asserted but not elaborated on, as if readers would take this for granted. I think both aspects of this characterization of Superman are mistaken: he often uses force, certainly, but never disproportionately, and always to assist law enforcement when he can rather than subvert it. Batman has been known to cross both of these lines and has been criticized for it--see Colin Smith's review of the recent Batman #17, for example--but Superman has always been a clear counterpoint to this.
As for the second point, it is indeed a common storytelling device in comics for heroes to go mad with power, succumbing to the Ring of Gyges and abusing their fantastic abilities. This is an everpresent issue for Superman, the most powerful of heroes while at the same time a visitor to our fair planet. But this is a feature rather than a flaw: it allows the ongoing creators of Superman to depict the human (and Kryptonian) struggle to retain one's ethics against the pull of self-interest, especially as the power to pursue the latter grows. This highlights the importance of Clark Kent's upbringing in Smallville, where the Kents instilled a solid moral code in Clark to counteract the temptation of using his powers later. Of course he may let his resolve slip and use his powers for himself or causes he comes to believe in. But because he's a hero--because he's Superman--he won't.
So yes, a writer such as Orson Scott Card could use Superman's power to further his own agenda. But let's keep the focus of our collective disgust on Mr. Card, not on a superhero that, for 75 years, has shown us consistently how one should use amazing power for the good of others despite every temptation to do the opposite.
