The story is an alternate history of what might happen if communists took over the United States, along with a history of communism in the Soviet Union/Russia.
Some choice excerpts:
"We should have done our thinking and praying before this happened."
"But with my wife working, who will care for the children?"
"Our latest directive from our superiors is to steal all anti-Communist books from our American city libraries."
"If the party wishes it, I will obey."
It has an introduction by none other than J. Edgar Hoover.
(link via BentleyBlog).