Permissive action links

Funny how sometimes you actually learn something from playing video games: One mission in the Fort Constantine level in Fallout 3 involves the launching of a nuclear ICBM (inter-continental ballistic missile, the launch code for which is "00000000". As it turns out, the so-called "Permissive Action Links" (another word for security locks to prevent unauthorized launches) for the nuclear arsenal of the United States were kept at all zeros until 1977. Another stunning account of Bruce Blair, whose Nuclear Recollections I have posted about recently.

Keeping Presidents in the Nuclear Dark (Episode #1: The Case of the Missing “Permissive Action Links”) - Bruce G. Blair, Ph.D.