Horowitz is a very brave and honorable man.
David Kengor has written a revelatory masterpiece called “Dupes” that should also be on your short list.
Enjoy.
Amazon says the author is “Paul Kengor.” Unfortunately, the book doesn’t show up in either of the library catalogs we use!
One of the surprises in Horowitz’s book was the ferocity of the left’s attack on anyone who made the slightest deviation from the party line. One toe off the reservation, and ZOT! They really are Stalinists, behind the multiple layers of lies.