Second Variety

"Second Variety" is a short story by Philip K. Dick first published in Space Science Fiction magazine, in May 1953. A nuclear war between the Soviet Union and the West has reduced much of the world to a barren wasteland. The war continues, however, among the scattered remains of humanity. The Western forces have developed "claws", which are autonomous self-replicating robots to fight on their side. It is one of Dick's many stories in which nuclear war has rendered the Earth's surface uninhabitable. The story was adapted into the movie Screamers in 1995.

The short story "Jon's World" written in 1954 revisited the claw-infested world of "Second Variety".

"Second Variety" occurs in the aftermath of an extensive nuclear war between the Soviet Union (sometimes referred to as Russia) and the United Nations. Early Soviet victories forced the North American government and production to flee to a Moon Base, leaving the majority of their troops behind. To counter the almost complete Soviet victory, U.N. technicians develop robots, nicknamed claws—the basic models are "a churning sphere of blades and metal" that ambush their unsuspecting victims "spinning, creeping, shaking themselves up suddenly from the gray ash and darting toward… [any warm body]." U.N. forces are protected from the claws by a special radiation-emitting wrist tab. Within six years, the sophisticated and independent claws have destroyed the Soviet forces, repairing and redesigning themselves in automated underground factories run without any human oversight.

The U.N. forces receive a message from the Soviets asking for a policy-level officer to go to them for a gravely urgent conference. The U.N. victory was costlier than they had expected. Major Joseph Hendricks is sent to negotiate with the Soviets. En route to the rendezvous, he meets a small boy named David who asks to accompany Hendricks. When they near the Soviet bunker, soldiers immediately kill the boy, revealing him to be an android. The claws' development program has evolved to develop sophisticated robots, indistinguishable from humans, designed to infiltrate and kill. The three Soviets met by Major Hendricks—soldiers Klaus, Rudi, and a young woman named Tasso—reveal that the entire Soviet army and command structure collapsed under the onslaught of the new robots - they are all that are left in the command center.

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Wikipedia