I am no expert on super heroes, but I didn’t think WW was from the U.S. Isn’t she from her own island nation?
Her outfit used to look like it was tailored from an American flag, but perhaps no longer.
Yes; originally called “Paradise Island”, but changed to “Themiscyra” in the comics. Diana is the “daughter” of Queen Hippolyta of the Amazons of Greek myth (fashioned as a clay baby and given life by the Greek mythical “gods” rather than being conceived the normal way), and as long as the Amazons stay on their island, they have immortality in the flesh, but when Steve Trevor, an ASUSA officer, crash-lands off the coast, Diana loses her immortality by falling in love with him and insists on going with him to the USA.