The Tomb of the Unknown Soldier is guarded twenty-four hours a day, three hundred and sixty-five days a year. It has been guarded, without interruption, since 1937. In September of 2003, Hurricane Isabel reached Washington. The National Park Service, out of concern, gave the sentinels of the Old Guard permission to stand down for the storm. They did not stand down. The sergeant of the guard on duty that night refused the permission, calmly, and without further comment. He would later say, in an interview, only that permission was not the same as an order, and that in the absence of an order, the walk continues. The walk continues. Twenty-one steps. Turn. Face the tomb. Twenty-one seconds. Turn. Face the other way. Twenty-one seconds. Twenty-one steps. The rain came sideways. A tree fell in the cemetery a hundred yards to the east. The wind lifted a portion of the roof from a nearby maintenance shed. The sentinel did not break stride. He walked. He turned. He walked. At 3 a.m. the wind reached seventy miles per hour, and a sentinel weighing 175 pounds in soaked wool, carrying a rifle, and wearing sunglasses in the dark because the manual requires them, walked twenty-one steps, turned, and walked twenty-one steps back. Nobody was watching him. Nobody could have watched him. The cemetery had been closed. The public had been evacuated. The only witness was the storm. He walked for six hours. He was relieved at 6:12 a.m. The tomb had not been left, at any point during the storm, uncovered. There is no medal for this. There is no ribbon. There is no citation. There is no commendation in his file. The Old Guard does not require one. The walk is the point. The walk was the walk before there was a country to record it, and the walk will be the walk after everyone who remembers this night is gone. Somewhere in America, at this moment, in whatever weather, a sentinel is walking twenty-one steps beside a marble slab, facing an unknown man whose name he does not know, for an oath he took to a country that will never see him take it. That is what the promise looks like when nobody is watching.