Sounds carry historical and political significance, even when they are intended as pure entertainment. Alternative meanings shimmer just beneath the surface as accepted meanings—safer meanings—give way to the attentive listener. Consider the sound of fireworks. According to Wikipedia, fireworks “were originally invented in ancient China in the 12th century to scare away evil spirits, as a natural extension of the Chinese invention of gunpowder.”

In the twenty-first century, fireworks and other forms of explosive entertainment continue to fulfill their ancient mandate to scare away “evil spirits.” When we pack a blanket and join our family and friends on the beach to experience the fireworks, we banish loneliness, depression and tiredness, as well as our anxieties about the economy, our worries about the country’s values and the concerns we have about the continuing wars in Iraq and Afghanistan. Yes, some of us will think about WWII or the Vietnam War and relive the sounds of those engagements. But for most of us, the sounds we hear haven’t come from personal experience. What we hear in our imagination comes from TV, the movies—maybe from books. The summer blockbusters, with their loud car chases, crashes, gunfights and jet fights—the video games, with their own explosive sound and imagery—they, too, banish evil spirits by conjuring them at a safe distance.

Here’s where the heavy slip-slide comes in: movie and video game technologies have become an integral part of the training our sons and daughters receive when they enter the military. And when they come back from war with psychological trauma and nightmares, the military will help them return to “normal life” by training them on therapeutic video games that simulate the audio and visual experiences of war, and help them relive these events in a safely controlled environment.

When I heard the fireworks exploding near my home yesterday I imagined the patriots battling on the Green in Lexington, Massachusetts. I also imagined a time when aristocrats picniced on hillsides while pitched battles were fought in the valley below. And I imagined that first burst of gunpowder in the “New World” as it must have sounded to a single native American standing on the shores of Hispaniola, watching the “Old World” approach.

Image: Yinka Shonibare MBE (b. United Kingdom, 1962). How to Blow Up Two Heads at Once (Ladies), 2006. From the Brooklyn Museum.