Not if Angry Nordic Jesus has anything to say about it!
Your blog on the National Shrine caught my eye. I'm an Arlington seminarian who's assigned to the Shrine for the summer, working as an assistant to the Director of Liturgy, Fr. Andrew Fisher, a fine Arlington priest (class of '98). In fact, there's a good chance you saw me running around the lower level of the Shrine on some errand or another! :)Anyway, in answer to your question... yes, hard as it is to believe, guitars have been played at Mass there. There was apparently a folk Mass there on Sundays when Fr. Dan Maher (2 liturgy directors ago, now our Episcopal Vicar for Finance in the Arlington diocese) arrived at the Shrine -- this would have been around 1994 or '95. He eliminated it, however.
The Catholic University of America campus ministry has Sunday Masses there as well. Though I've heard they've improved tremendously (when I first served at the Shrine before I entered seminary, about 6 years ago, I used to hear horror stories about their Masses), they may well play the guitar too. Yikes.
The good news: at any official Shrine liturgy, you're not going to hear a guitar.
What a blessing it must be to be assigned to the Shrine during a summer while you are in the seminary! I don't think I would ever want to leave! Well, unless God wanted me to leave in which case I would. This reader is a classmate of another seminarian friend of mine who is at Blessed Sacrament in Alexandria this summer.
I poached the expression "Angry Nordic Jesus" from Emily Stimpson. I happen to think that mosaic (link to a picture of it above) is wonderful and terrible. Terrible in the sense of awesome and frightening. It inspires the fear of God - awe and wonder in His presence. I don't know how anyone could play a guitar in the Shrine with him looking down!
