Hawaii's false alarm about an imminent missile attack isn't the first time a glitch made it look like the missiles were on the way. There were some even scarier false alarms during the Cold War that could have easily led to nuclear holocaust if military officials hadn't figured them out.

A few of the worst ones, as told in "Raven Rock," author Garrett Graff's account of the U.S. government's plans to survive a nuclear war:

• November 1979: NORAD computers detected what appeared to be hundreds of Soviet missiles headed toward the U.S. It turned out that someone had accidentally stuck a training tape into the computer system.
• June 1980: The computers appeared to show 2,200 incoming Soviet missiles — "a full-scale general nuclear attack." This time, the alarm was blamed on the failure of a 46-cent computer chip.
• September 1983: Soviet warning systems showed five U.S. missiles that appeared to be heading toward the Soviet Union. In reality, its satellites saw the sun's reflection off of clouds and thought it was a missile launch.