Sixth Column, alternatively titled The Day After Tomorrow, is a short novel by Robert A. Heinlein Originally published as a serial in Astounding Science Fiction (January, February, March 1941, as by Anson MacDonald) it was published in hardcover in 1949. The novel follows the tried and true Yellow Peril storyline of an invasion/occupation of North America by East Asians, and in this case by the PanAsians, an abusrd fusion of the Chinese and Japanese.