For years, sentinels guarding the Tomb of the Unknowns at Arlington National Cemetery voluntarily had their lives defined by four constant and silent witnesses: the Unknown of World War I, the Unknown of World War II, the Unknown of the Korean War, and the Unknown of the Vietnam War. Until 1998. That’s when the Unknown of the Vietnam War was identified as First Lieutenant Michael Joseph Blassie. The tombs—the first of which was erected in 1921—represent the American soldiers who died in conflict and were never identified. Blassie was originally tallied as one more unidentified service member lost to the war, either missing or killed in action. In the longer course of history, however, he came to occupy a place at the nexus of old and new in how the United States cares for its dead.