In the days and weeks after the 9/11 tragedy, musicians responded in the only way they knew how. They played. For the dead, for the injured, and for all of us who were struggling to cope with the enormity of what had happened. In today's show, we look at how the nation responded through music to the horrors of September 11, 2001. And we'll hear several new works written in commemoration of the 10th anniversary of the attacks.