Sunday, December 7, 1941 – 06:15
Many citizens of Honolulu remained unaware of the true state of affairs for at least an hour after the attack began. Accustomed to the roar of aircraft and explosions from Army and Navy exercises, they accepted the racket as no more than unusually realistic maneuvers. The radio warnings were not specific enough to spell out the situation for the average civilian.

At Dawn We Slept: The Untold Story Of Pearl Harbor