Depends what you think it means to be political, I reckon.

The number of folk songs that are overtly political (Rigs of the time, & that) is quite small. However, as Les said earlier, keeping a tradition alive is a political act in itself.

We live in an age of multi-million pound industries (advertising, telly & that) which are devoted to conditioning our responses, and trying to make us pin our hopes & desires on a certain set of products & aspirations. Now, I'm not going to pretend that folk music is somehow entirely outside that system of control (the pile of CDs next to my stereo look suspiciously like commodities to me).

However, to participate in the creation of an alternate world of meaning (which is what I think happens in a good folk gig or session) is in some sense saying, "You know what? There's more life that a new car." And I reckon that counts as political.

Of course, there are other subcultures (or taste cultures, if you like) that can do the same thing.