Two points:
The Japanese did send a Declaration of War for the Japanese ambassador to deliver to the White House an hour before the attack, but there were only two people cleared for decoding the encrypted cable, and neither one was a typist. They delivered the cable late.
The Japanese Navy did not send the follow-up attack on the Navy fuel depot and maintenance facilities because the American aircraft carriers were not it port, and Admiral Yamamoto decided not to risk his fleet being found by the enemy carriers.
Thanks for the calrifications. I just remember reading something to the effect of what I posted years ago, which is why I wanted to make it clear I was pulling this from memory.