"....whereby individuals of any stripe can enjoy the music without being browbeaten by political opinion. "
Sorry, folk song has always contained its fair share of politics, be it Jacobite, anti-establishment, fight for better conditions, recognition of and opposition to class differences, struggles for national independance, pro-industrial action, support for and opposition to military activity (want a list of American Civil War songs - either side available) - right down to children's songs and election chants "Vote-vote-vote for....." whoever, or the more sophisticated "Harry was a Bolshie"). Perhaps you meant to say 'left political opinion'?
As somebody has already said, if you want to avoid politics, you're in the wrong game. Try macrame (was going to say chess, but it don't come more political than that).
Jim Carroll