From what I read it was a delay caused by the decoding of the declaration of war... that was multiplied due to the length and the sophisticated words used... it wasn't OI! YOU! I DECLARE WAR! it was The Imperial Nation of Japan..... yadayada yada political sperl that stuffed it and it was a sneak attack they didnt want the bases to prepare themselves before the attack was made hence it was timed to be 30 mins after... so mobilization could not occur increasing the damage done.... Still gutless *******s though