Old Glory

There was a time in America a woman could purchase a white bra with the strap ends unfinished.  It had a slide where you could make the strap longer or shorter.  If the strap end was visible at the neck line (or shoulder on a short sleeve top) it was considered embarrassing.  'Your flags are flying' meant your undergarments are showing.  It wasn't ladylike.  It was also considerate to let other women know they were being overly patriotic.  Back then 'keeping the old flag up' was thought of as a national duty, but without advertising.

Star Rider Foreigner