Art reflects the culture it’s created in. In the ’30s and ’40s, directors like Frank Capra produced optimistic comedies and dramas to help uplift a national morale brought low by the Great Depression and World War II. In the late ’70s and ’80s, punk music and hip-hop spoke to political frustrations. Part of the value of the art that makes up popular culture is what a piece of music, literature or cinema can tell us about the prevailing cultural attitudes at the time it was...