When MLK gave that famous speech in 1963...
Bernie Sanders was there:
Burlington Free Press: How had you originally gotten involved in civil rights causes? What started it all for you?
Bernie Sanders: It was a question for me of just basic justice the fact that it was not acceptable in America at that point that you had large numbers of African Americans who couldnt vote, who couldnt eat in a restaurant, whose kids were going to segregated schools, who couldnt get hotel accommodations, living in segregated housing. That was clearly a major American injustice and something that had to be dealt with.
BFP: Did you realize at the time, as you were on your way, that the March on Washington would be as big or significant as it was?
BS: There were hopes that a huge number of people would come out and that it would play a role in moving the government to the Voting Rights Acts, other efforts to end segregation and Jim Crow in America. So that was the hope, and I think when we got there and saw so many people, I think we felt very positive and kind of had the belief that something important was going to come from that.
http://www.burlingtonfreepress.com/article/20130824/NEWS07/308240004/-1/rss?utm_source=dlvr.it&utm_medium=twitter&gcheck=1
He was concerned about civil/voter rights 50 years ago.