I would have thought 'The answer, my friend, is blowin' in the wind' means 'The answer cannot be known, cannot be grasped, just as the wind cannot be grasped and we cannot predict where it will blow'. I would have thought this would be very meaningful in the context of 1960s civil rights, with people fighting hard for and against things with no definite time of achievement to look forward to.

Surely the thing about a lot of great art is that it is multivalent and is open to many applications, just as much traditional music is.

One other thought. Bob is Jewish, as everyone knows. In both Hebrew and Greek the word for wind also means breath and spirit. So the answer is in the wind, our breath, in the spirit. But I may just be trying too hard here!