Glueman makes some valid points regarding heterodox traditions in the US and the difficulty (impossibility?) of speaking of Tradition with a capital 'T' (if I read him correctly). Even within the English-speaking ballad tradition over here there's a lot going on (I just listened to an African-American version of House Carpenter, accompanied with banjo). Looking for an 'ideal form' of an 'anglo-american' ballad would be like looking for an ideal, platonic cow out there in the ether somewhere. Not that 'pure forms' really exist anywhere, it's just much more difficult to pretend in America. I would expand on his argument and note that while the varied forms of American popular music evolved from vernacular forms, English popular music is based (ironically) upon American vernacular music as well. So maybe that's where this 'identity crisis' comes from; maybe 'What is Folk?' is another way of asking 'Who Are We?' for some people.