Two phenomena: anti-Semitism and American class conflict. Is there any connection between them? In a letter to this newspaper, the noted venture capitalist Tom Perkins called attention to certain parallels, as he saw them, between Nazi Germany's war against the Jews and American progressives' war on the "one percent." For comparing two such historically disparate societies, Mr. Perkins was promptly and heatedly denounced.

But is there something to be said for his comparison—not of Germany and the United States, of...