On July 9, 1962, Hawaii was hit by a massive electromagnetic pulse (EMP) attack, which within minutes took down the state’s communications systems and traffic lights —  virtually everything that ran on electricity. The EMP wasn’t an attack by a foreign government; rather the U.S. government had set off a 1.4-megaton nuclear warhead at a height of 248 miles above Johnston Atoll in an operation the military named “Starfish Prime.” The test caused radio disruptions in Hawaii, California, and Alaska, and knocked out six satellites above the Pacific.

“No one expected the test to impact Hawaii, because it was 850 miles away,” said Toby Clairmont, deputy administrator for the Hawaii Emergency Management Agency, which is located within one of Hawaii’s most recognizable landmarks, Diamond Head. “This kind of blast does not hurt people, but as we’ve seen, it shuts down power and phones and goes after infrastructure and could cause problems at medical facilities.” READ MORE