Frankly, the banjo does not need any defense. Just look at some of the people who have excelled at playing the banjo...Pete Seeger, Earl Scruggs, John Hartford and many other folk/bluegrass icons. If the banjo is good enough for them, than it's good enough for anyone.

I've heard Bela Fleck play everything from classical to jazz on the banjo and all forms of music sound wonderful on it. A different interpretation than what one is used to hearing perhaps but excellent in its own right. Granted the banjo does not sound like a concert piano when classical music is played on it or like a sax or guitar when jazz is played on it or like a fiddle or guitar when folkbluegrass music is played on it but who has decreed that those instruments are the ones most acceptable for that style of music.

Nothing will ever convince a banjo hater to like the instrument so why even waste the time trying. I feel bad, however, for those individuals who are so close minded that they can't accept a wonderful sounding instrument for what it is. The banjo isn't going away no matter what they think so it's their loss.