http://www.comicsalliance.com/2011/04/27/superman-renounces-us-citizenship/
"... It doesn't seem that he's abandoning those values, however, only trying to implement them on a larger scale and divorce himself from the political complexities of nationalism. Superman also says that he believes he has been thinking "too small," that the world is "too connected" for him to limit himself with a purely national identity. As an alien born on another planet, after all, he "can't help but see the bigger picture."
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