Working: Researching, Interviewing, Writing by Robert A. Caro:
When I was asking him about what the three aides heard on the ride to the Capitol, Buzz at first—and second, and third, etc.—replied, Well, nothing. He didn’t say anything. So I said something like, So the ride was in complete silence? And then he finally said, “Well, I guess except for when the car passed out through the gates.” He meant the gates of the White House onto Pennsylvania Avenue to turn right and go to Capitol Hill. The pickets were there. And Buzz said, Well, they were singing “We Shall Overcome.” And they sang it as we came out, “as if,” I wrote, “to tell Lyndon Johnson to his face, ‘We’ll win without you.’” Busby and Goodwin said Johnson never looked up as they passed the pickets. But Busby knew Johnson, and he knew his expressions. So I said to Busby, Well, did he hear them? And Busby said, He heard them.
And of course the speech that Johnson gave is one of the greatest speeches, one of the greatest moments in American history. I watch it over and over. I’m thrilled every time. He said, “Their cause must be our cause too. Because it is not just Negroes, but really it is all of us who must overcome the crippling legacy of bigotry and injustice. And we shall overcome.”