You can hear a long interview with Michael Novak on Vatican Radio here.
Also on that page you will find a link to an interview with Father Stan De Boe, of the Conference of Men’s Superiors, who complains about the Novak invitation. Fr. De Boe suggests that the State Dept. inviting a Catholic theologian to speak in the Vatican City is a violation the separation of church and state (even though he is a layman, speaking as a private citizen, and works for a secular institution). Fortunately the interviewer (Vatican Radio’s Charles Collins) doesn’t let him off easy.