The Folk Tradition
At the end of the War Between the States, the murder of Laura Foster and subsequent hanging of Tom Dula (pronounced "Dooley" around Wilkes County, North Carolina), drove local poet, Thomas C. Land, to pen the ballad that became an Appalachian standard. Hang Down Your Head, Tom Dooley was revived and brought to worldwide attention when the Kingston Trio recorded it in 1958.
In the 1960s folk music was very political. Even the Smothers Brothers television show was cancelled due to their anti-war sentiments. (Someone remind me to post something by the Smothers Bros. sometime, I loved their show.)
With so much going on here on our little planet nowadays, it was just a matter of time before the events of the day made their way into song.
It's the folk tradition.