For Canada Day, The Red Ensign, a patriotic WWII superhero. From True Patriot, an anthology of Canadian superhero stories, featuring flag-bearers, ancient myths, and Superhero Girl vs. Canadian-ness.
WWII superheroes like Captain America stand out a bit from other Golden Age characters, being more tied to a specific era. And of course fighting Nazi supervillains and weird science and sometimes entire armies. Cap being a man out of time defines him in his modern adventures.
And most players will happily take the chance to punch some Nazis.