Music: Left-Wing Wagner

Germany's Bayreuth Festival had not seen anything like it in years. Instead of applause for Richard Wagner's music, there were hisses and catcalls —led off by an ear-shattering "No!" from the box of Dr. Alfons Goppel, Bavarian minister-president (equivalent of a U.S. Governor). Women lost their jewelry in the tumult, and one man furiously tore up $250 worth of tickets for subsequent performances.

Wagner, a musical and political revolutionary who liked nothing better than a good row, would probably have loved it. Whether he would have loved what Bayreuth did to his Tannhäuser, the...