“Pearl Harbor would have been legitimate. It was still a dirty move to bomb it without a formal declaration of war.”
“Good” King FDR took care of that by blockading Japan.
Pearl Harbor was was still a surprise sneak attack. Yes there was a build up and an expectation that diplomatic relations would be broken and war declared.
However, it was arrogance and incompetence which made the Japanese late in their declaration. If they wanted to be considered honorable enemies they would have done things in a timely manner. Trying and failing to get a formal declaration of war to us an hour before was simply not good enough.
Its all old history at this point, and no apology should be expected at this point. But the Pearl Harbor attack was still a dirty move done by an enemy empire bent on total war.
Japan used it's military aviation forces to attack the armed forces of another sovereign nation on that nation's soil without a declaration of war and without having had a justifiable cause to go to war.
In other words, exactly what John F'n Kerry has been repeatedly asking to do in Syria.