As you can see from the previous post, I am wondering whether Strauss was an esoteric writer and, if he was, what his esoteric teaching was. Melzer's book is helping me to think through this, although he's a little confusing on these points.
Although he does not say so explicitly, Melzer intimates that Strauss was what Catherine and Michael Zuckert would call a Midwest Straussian.
Consider the alternatives. If Strauss had been a West Coast Straussian, then he would have believed that the modern liberal regime was actually the fulfillment of ancient political thought. So he would have agreed with Will Altman that the superiority of liberal democracy was taught by Plato in Book 8 of The Republic in describing democracy as the one bad regime that was open to the philosophic life. In fact, in "Persecution and the Art of Writing," Strauss identifies the Athens of the fifth and fourth centuries B.C. as "comparatively liberal" (33), thus suggesting that modern liberalism might be a fuller expression of the liberal freedom provided by ancient Athens, in which there was plenty of room for open Socratic philosophizing until Socrates provoked the city at the end of his life.
If Strauss had been an East Coast Straussian, he would have been an esoteric writer, and his esoteric message would have been that liberalism is based on a delusional denial of the human reality that the philosophic life is dangerous for most people. Presumably, that esoteric message would have included advocacy of an illiberal regime, which is what Altman sees in Strauss's writing.