There are several ways in which a public performance of the Star Spangled Banner may be spoiled for its audience. Singing it at a slow tempo is among the worst, as it may make it seem as though the performer loves the sound of his or her own voice more than the honor and dignity of America.
For an arrangement in 3/4 time, the tempo should be at least 90 beats per minute.
The Flag Code lists many voluntary practices that demonstrate respect for America's best known visual symbol. It's time that everyone be made aware that singing the anthem under tempo is equally disrespectful.