Masao Asada had just finished delivering groceries around Pearl Harbor, Oahu, when he heard some huge booms. No big deal, he thought—he was used to hearing noise from dredging activity in the Pacific Ocean lagoon. But the booms kept coming.

Asada jumped in his truck and drove toward the pier used by the U.S. Navy and Army. En route, he was flagged down by the driver of another car. “Get out of here!” the man shouted, Asada recalled in an oral history taken years later. “This is not practice! It’s war.” That’s when Asada looked to the sky and saw Japanese warplanes zooming overhead.

The grocery store owner was one of the thousands of eyewitnesses to Japan’s surprise attack on