Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Harrowing

One of the most harrowing books I've ever read. An amazing entreaty against violence of both the left and the right, and a heartbreaking analysis of contemporary anti-Semitism. Comparable at some points perhaps to Koestler's Darkness at Noon, except that it deals with torture in a more direct (and horrifying, since it's nonfiction) way. I wish this were required reading in schools.