For the two weeks of the Folklife Festival, the United States capital is the destination for an idea that began over 2,000 years ago, when the Silk Road became an economic thoroughfare, a conduit of knowledge and culture, a network, a myth perfumed by spices and resplendent in silk. When Yo-Yo Ma and the Silk Road Ensemble perform, or when an unknown folk group from Kazakhstan plays to an American audience, we are moved because we understand, in those transcendent moments, how we all connect, and what our true responsibilities are to each other. We also feel a poignant anguish at the realization that, too often, we do not take these ...