Vice President Joe Biden steps off Air Force Two, a Boeing C-32, at Joint Base Charleston, S.C., Dec. 3, 2015. Biden visited the Lowcountry to pay tribute to Joe Riley, who is retiring after 40 years as the City of Charleston mayor. (U.S. Air Force photo/Senior Airman Jared Trimarchi)

Vice President Joe Biden is greeted by Capt. Timothy Sparks and Col. Jimmy Canlas at Joint Base Charleston, S.C., Dec. 3, 2015. Biden visited the Lowcountry to pay tribute to Joe Riley, who is retiring after 40 years as the City of Charleston mayor. Sparks is the Joint Base Charleston deputy commander and Canlas is the 437th Airlift Wing vice commander. (U.S. Air Force photo/Senior Airman Jared Trimarchi)