In 1965 the SCLC joined a voting-rights protest march from Selma, Alabama, to the state capital of Montgomery, more than 80 km (50 mi) away. The goal of the march was to draw national attention to the struggle for black voting rights in the state. Police beat and tear-gassed the marchers just outside of Selma.
Televised scenes of the violence, on a day that came to be known as Bloody Sunday, resulted in an outpouring of support to continue the march (Selma). The SCLC petitioned for and received a federal court order barring police from interfering with a renewed march to Montgomery.
Two weeks after Bloody Sunday, more than 3,000 people, including a core of 300 marchers who made the entire trip, set out toward Montgomery. When they arrived five days later, King addressed a rally of more than 20,000 people in front of the capitol building.
The march in Selma created support for the Voting Rights Act of 1965, which President Lyndon Johnson signed into law in August. The act suspended (and amendments to the act later banned) the use of literacy tests and other qualification tests that often had been used to prevent blacks from registering to vote.
After the Selma protests, King had fewer dramatic successes in his struggle for black civil rights. Many white Americans who had supported his work believed that the job was done. In many ways, the nation’s appetite for civil rights progress had been filled. King also lost support among white Americans when he joined a growing number of antiwar activists in 1965 and began to criticize publicly American foreign policy in Vietnam.
King’s outspoken opposition to the Vietnam War (1959-1975) angered President Johnson. On the other hand, some of King’s white supporters agreed with his criticisms of United States involvement in Vietnam so strongly that they shifted their activism from civil rights to the antiwar movement.