I’m reading Robert Caro’s book Working, about his experience writing his magisterial multi-volume biography of Lyndon B. Johnson. This passage on page 165 caught my eye:
One [song of the 1960s] is a song that had been sung for a long time …. It’s “We Shall Overcome,” of course. …
… [D]uring the 1950s, it was taught at the Highlander Folk School in Tennessee, a school created to teach people how to organize in the labor unions, and to teach civil rights workers how to fight for their cause. The legendary folksinger Pete Seeger came to sing it there.
…[Seeger] changed “We will overcome” to “We shall overcome.” That change shows the power of words. Changing a single word—changing “We will overcome” to “We shall overcome”—makes a big difference to the song.
Caro is right; I’d heard early versions of the song as We Will Overcome and thought that it didn’t have the same power as We Shall Overcome.