A “Broken Arrow” is defined as an unexpected event involving nuclear weapons that results in the accidental launching, firing, detonating, theft or loss of the weapon.
Communication between the Strategic Air Command headquarters (SAC HQ) and NORAD failed abruptly, resulting in the loss of connection with three Ballistic Missile Early Warning Sites (BMEWS) supposedly running on independent lines of connection. A Soviet nuclear first-strike had to be assumed. It was later discovered that an AT&T switch in Colorado caused all systems to fail simultaneously. A response was only averted by direct communication from a US bomber with one of the BMEWS.
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