The Capitol Christmas Tree is lit on the west front lawn of the Capitol in Washington D.C., the United States, Dec. 4, 2019. The Capitol Christmas Tree has been a tradition since 1964. (Photo by Ting Shen/Xinhua)

The Capitol Christmas Tree is lit on the west front lawn of the Capitol in Washington D.C., the United States, Dec. 4, 2019. The Capitol Christmas Tree has been a tradition since 1964. (Photo by Ting Shen/Xinhua)

The Capitol Christmas Tree is lit on the west front lawn of the Capitol in Washington D.C., the United States, Dec. 4, 2019. The Capitol Christmas Tree has been a tradition since 1964. (Photo by Ting Shen/Xinhua)

The Capitol Christmas Tree is lit on the west front lawn of the Capitol in Washington D.C., the United States, Dec. 4, 2019. The Capitol Christmas Tree has been a tradition since 1964. (Photo by Ting Shen/Xinhua)

The Capitol Christmas Tree is lit on the west front lawn of the Capitol in Washington D.C., the United States, Dec. 4, 2019. The Capitol Christmas Tree has been a tradition since 1964. (Photo by Ting Shen/Xinhua)