Senior Master Sgt. William Tortolano, Strolling Strings’ violinist, performs for a crowd at the National Museum of American History in Washington, D.C., July 16, 2015. The U.S. Air Force Band’s Strolling Strings concert was part of the museum’s Star-Spangled American Music Series. (U.S. Air Force photo/Airman 1st Class Ryan J. Sonnier)