We just moved here from Northern Virginia and we have visited Arlington Cemetery many times. One time we met an American family who lived in New Zealand and I said they would enjoy seeing the changing of the guard at the Tomb of the Unknown Soldier, where a member of the Honor Guard guards the Tomb 24 hours a day. A teen-ager in the family said, "What's the point of that?"
To be honest, I was flabbergasted. I didn't know what to say. I do know that we have seen many, many people watch the changing of the guard. From the look on their faces, I think they all know what it signifies.
Here is a video that you may like, about two veterans buried at Arlington.
G.I. Joe & Lillie - The Oak Ridge Boys - YouTube