Protest songs, were they political?
They are certainly anti-establishment, but as the establishment can change after elections, that makes it apolitical surely?
Looking at it from my side of the ditch, the US seems to split into several political camps, musically. My perception is that folk musicians, and remember that what is classified as folk in the US doesn't always coincide with what is classified as folk over here, seem to be left leaning, while country music seems to lean the other way.
Over here the folk scene seems to be almost 100% left wing.

Yes generalisations I guess, but as I am not a political animal myself, it's the best I can do.