As a visiting professor in Germany in 2011, I found myself alone above the gravestone of Richard and Cosima Wagner at Wahnfried, the couples’ legendary home in Bayreuth. I was studying the corrosive influence of the cult of genius on the Nazis. The anti-Semitic Wagner, however beautiful his music, played a central role in that dark tale. It was dusk. Not a soul was on the property. I had a bladder full of Helles. It was an opportunity to make a mark.