X-Men and the Circumstances of Justice

— There is a massive rash of philosophical comic geekdom breaking out in the blogosphere over the arrival of the new X-Men movie. See, for example Matthew Yglesias and Jacob Levy. As I am a philosophical geek who bought his first issue of X-Men almost 20 years ago for I think $.65 (It had the Juggernaut in it), I will do my part…
Among Hume's “circumstances of justice” is the requirement that there be no great asymmetries in power. “Moral standing” requires that a party to an agreement be able to contribute and gain roughly equally from cooperative agreements, and be roughly equally disposed to comply with those agreements. We are not in the circumstances of justice with young children and the severly handicapped, and this entails that for certain purposes they lack moral standing. Now, are homo sapiens and homo superior in the circumstances of justice with respect to one another, or do we mere humans lack moral standing relative to certain mutants with massive powers? Given a contractarian framework sensitive to the Humean requirements, is the moral message of the X-Men even intelligible? Does the massive asymmetries in power introduced by the story render the underlying analogy with the struggle for civil rights moot?