Even though the majority of Americans want real health care reform, an end to militarism, and accountability for crimes, we won't get them unless we can mobilize enough people to protest and demand change.
Here are some lists of songs concerning the Vietnam War
http://en.wikipedia.org/wiki/Anti-war_songs#Vietnam_War
And here's an article about protest songs in general:
http://en.wikipedia.org/wiki/Protest_songs
Dave Hajdu wrote an article, Music in the Meltdown, comparing the musical response to the Great Depression to the musical response to the current economic crisis.
Interestingly, "We Shall Overcome" was adopted worldwide by all sorts of protest movements.
(Note: You can view every article as one long page if you sign up as an Advocate Member, or higher).