Joe Biden marks 9/11 anniversary with tribute, call for unity September 11, 2021 at 03:35AM

US President Joe Biden is making an appeal for the nation to reclaim the spirit of cooperation that sprung up in the days following the 9/11 terror attacks as he commemorates those who died 20 years ago. Biden was a senator when hijackers commandeered four planes and exacted the nation's worst terror attack in 2001. Now he marks the 9/11 anniversary for the first time as commander in chief.