Address Unknown, small book with a big impact

Address Unknown by Katherine Kressman Taylor was first published in 1938 and was an immediate sensation. This short epistolary novel traces the correspondence between two German American friends: a Jew who remains in the United States and his friend who returns to Germany and gradually succumbs to the Nationalist rhetoric and anti-Semitism of 1930's Germany. The destruction of their friendship reflects the broader political picture. The Nazi betrays his American friend who, in a clever twist at the end of the book, exacts a revenge through letters intercepted by the German censors.
Library Journal calls this "one of the earliest pieces of Holocaust fiction." Barnesandnoble.com writes, "Address Unknown is a haunting tale of enormous power and enduring impact."
This small book would be a good choice for book groups, perhaps paired with another, longer work of Holocaust literature.