flag n. a piece of cloth or similar material used as the symbol or emblem of a country or institution.
Because a flag is a flat object, it may signify flatness or the relative lack of depth in much modernist painting. The flag may of course function as an emblem of the United States and may in turn connote American art, Senator Joseph McCarthy, or the Vietnam War, depending on the date of Johns’ use of the image, the date of the viewer’s experience of it, or the nationality of the viewer. Or the flag may connote none of these things. In other words, the meaning of the flag in Johns’ art suggests the extent to which the “meaning” of this subject matter may be fluid and open to continual reinterpretation.