The Iron Heel describes the fall of the United States to a cruel fascist dictatorship. Fearful of the popularity of socialism, the plutocrats of the Iron Heel conspire to eliminate democracy and, with their secret police and military, terrorize the citizenry. They instigate a German attack on Hawaii on Dec. 4, 1912; as socialist revolutions topple capitalist governments around the world, the Iron Heel has 52 socialist members of the U.S. Congress imprisoned for treason. Elements of London's vision of fascism, civil war, and governmental oppression proved to be prophetic in the first half of the 20th century and the first part of the 21th as well.