I don't know, maybe you treated this subject before but there are many heroes who carry the colors of their respective countries :Captain America, Iron Patriot, Captain Britain, Vindicator, Sabra, Collective Man, Uncle Sam... It could be an idea for a contest, create a figure existing or original who symbolizes a country.
We could call this "Heroes Nations"... Ok !! Let's find another title, this one sounds like a video game. :-)