Question mark?

We sing only the first stanza of Key's song, but the Star-Spangled Banner actually has four verses. Only the first stanza ends with a question mark. You can read the other four stanzas, which include plenty of exclamation marks but no question marks.
Today some people choose to interpret Key's words—and the question mark—more broadly, not just as a question of whether the flag is still flying, but as a moment to reflect on whether we are upholding the ideals embodied in the vision of America as the land of the free and the home of the brave.