In nearly every city, town, village across the U.S., there will be celebrations with fireworks, food, speeches and especially music—which is the focus of tonight’s forum, titled “Crossing Borders: The Music That Made Us American.” We’ll trace the history of some of the best-known songs and musical styles of this country—and especially the depth and diversity that developed when we were willing to learn from one another across lines of race, culture, class, and national origin.