What is FOLK music?

I've been trying to work it out, being a folk music promoter and all, what exactly is folk music? A lot of the subject matter is so dated, sailors and lords, lovely melodies notwithstanding!    What relevance to us these days? And all those high moralistic ballads - good for a time when there wasn't TV, magazines etc to educate young lads and lasses in the pitfalls of unmarried liaisons and heading off under false promises - they served a good purpose then, but what now?.... When does a songwriter cross the boundary and become a folk singer (cyril tawney for example)?  do we have to spend our lives in the armed forces, in the hills or whatever, or can we sing about our real life experiences as they are now in modern society?........Do we have to only sing songs that were collected by Lomax, Sharp and all the others? there's only so many ways to reinterpret and recompose what has gone before.....