US-HISTORY-POLITICS-RIGHTS-RACISM

US President Barack Obama (2L) and US Representative John Lewis (L), Democrat of Georgia and one of the original marchers, sing as they lead a walk across the Edmund Pettus Bridge to mark the 50th Anniversary of the Selma to Montgomery civil rights marches in Selma, Alabama, March 7, 2015. US President Barack Obama rallied a new generation of Americans to the spirit of the civil rights struggle, warning their march for freedom "is not yet finished." In a forceful speech in Selma, Alabama on the 50th anniversary of the brutal repression of a peaceful protest, America's first black president denounced new attempts to restrict voting rights. AFP PHOTO/ SAUL LOEB (Photo by Saul LOEB / AFP) (Photo by SAUL LOEB/AFP via Getty Images)