Fireworks, parades and backyard barbecues are a given these days with July 4, but that wasn't always the case. In the past, the holiday revolved around politics and social change, according to political historian Jon Grinspan. "For the first hundred years, you get a revolutionary holiday where there's a lot of raucousness in the streets, a lot of world-turned-upside down, a lot of class politics, a lot of racial politics," said Grinspan, a curator at the Smithsonian National