Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Extraordinarily powerful

A Canticle for Leibowitz is an extraordinarily powerful book. Its message, once one cuts past the Catholic overtones, is one that applies as much today as it did in the fifties, perhaps even more so than it did then, in light of the insanity in India and Pakistan. If ever there was a stronger literary work against nuclear war, I have yet to see it.