American First Ladies have traditionally worn black when meeting the pope in an official capacity. Only in the later half of the 20th Century and afterward have American presidents met popes face to face. The advent of air travel has allowed this to happen.
To read a presidential etiquette insider's blog on the subject click here. NPR has a wonderful primer on meeting the pope. In it are bits of wisdome like
What if the pope approaches me?Don't just stand there — genuflect. That means bend at the knee, for you non-Catholics.
To read the entire list of suggested manners click here.
Jackie Kennedy had a private audience with the pope, but I'm not sure weather it was John XXIII or Paul VI. The footage here is of Jackie with John XXIII.
Nancy Reagan met John Paul II with her husband in 1982. To see this short, historic video, click here.
|This was not from the 1982 meeting, but a more informal occasion later|
in the Reagan presidency
|The Clinton's and John Paul II|
|The Bushes with Benedict XVI|