US President Barack Obama walks alongside Amelia Boynton Robinson (R), one of the original marchers, First Lady Michelle Obama (L), and US Representative John Lewis (2nd-L), Democrat of Georgia, and also one of the original marchers, across the Edmund Pettus Bridge to mark the 50th Anniversary of the Selma to Montgomery civil rights marches in Selma, Alabama, March 7, 2015. The event commemorates Bloody Sunday, when civil rights marchers attempting to walk to the Alabama capital of Montgomery to end voting discrimination against African Americans, clashed with police on the bridge. AFP PHOTO / SAUL LOEB (Photo credit should read SAUL LOEB/AFP via Getty Images)
