proof the Pearl Harbor attack was allowed to happen

I understand the film from the Japanese perspective. That makes sense. But the footage from the American perspective indicates that cameras were set up in the right places beforehand. Movie cameras back then were large, expensive, and had to be operated manually. Thus, the US knew the date and time of the attack and was ready to record it well in advance. I'll add that the US had broken Japanese naval and diplomatic codes and thus knew an attack was imminent. 

WW2 - Attack on Pearl Harbor