Superman is no longer an American. To be honest, I didn't know he claimed to be. Anywho, in the milestone comic, Action 900, Kal-El renounces his US citizenship because he feels it will be better for other nations if he's global.
That's a big step for a hero that has been defined by this country. I understand Supes decision. Wonder Woman and Storm are also non-Americans. They claim their home 'countries'. But those two are different in the eyes of non-comic folk; so I wonder what impact this decision will have?
Oh, you may want to pick a couple of these comics. They are starting to sell out.