Virtually everyone has heard numerous songs that contain social or political messages. In fact, protest songs are a well-known song genre.
I think that while all songs have some kind of message, some scream out very specific ones. In fact, one that always seems to come back to me all the time is Martina McBride's Concrete Angel and the subject of child abuse as the initial post briefly mentioned. I think it would be pretty neat to create a list of songs that have important messages to us in this thread with a link. It could be social, environmental, political, etc... keeping things appropriate of course.
Martina McBride - Concrete Angel