Nothing gets some folks hackles up like a healthy dose of politics in comics. Particularly if those politics could be somehow construed as "un-American". Well, in Action Comics 900, David Goyer writes a story which sees Superman renounces his American citizenship after becoming involved in peaceful protests in Tehran which cause ructions for his adopted country. Supes comes to believe that being explicitly seen as a force for the US(be it good or bad) can no longer ensure the safety of the entire world..
Interesting stuff. And brave in my opinion. But I'm sure some would see it differently. As Bleeding Cool points out, a while back when Wonder Woman's new costume sported one less star on it Fox News almost had a hernia, and described her as un-American , unpatriotic and some going so far as to call her a communist. Their reaction to this should be pretty funny if and when they get wind of it.