Remembering US Prisoners of Warbr and Those Missing in Action.br On the third Friday of September, the United States observes a day of remembrance for those who were prisoners of war (POW) or those who are missing in action (MIA). .br This year’s National POWMIAbr Recognition Day is held on Sept. 18.br On National POWMIA Recognition Day, br the National League of Families’ POWMIA br flag is flown. .br The flag symbolizes the country’s remembrance of those imprisoned or still missing due to conflicts of war. .br According to the Defense Department’s POWMIA Office, 1,741 Americans are listed as missing and unaccounted for from the Vietnam War. .