Earlier this week, a sentinel reprimanded a group that included US Defence Secretary Pete Hegseth at Arlington National Cemetery. The incident followed a wreath-laying ceremony marking Veterans Day.
The Pentagon have since announced that Hegseth has given the soldier, Specialist Thomas Iglesias, a Joint Service Commendation Medal "for the execution of his duties at the Tomb of the Unknown Soldier".
BBC's Bernd Debusmann breaks down why Hegseth's group was reprimanded, the history behind the strict rules governing visitor behaviour and the importance of maintaining an atmosphere of silence at the Tomb of the Unknown Soldier.