Even "what-if" questions have to have some basis in historical fact or they're meaningless and can't serve as a departure point for conjecture. As I've pointed out, there is no historical basis for supposing that five carriers might have been at Pearl Harbor on December 7, 1941; as stated the question is pointless. I could, with equal basis in reality, claim that Roosevelt would simply put 3,000,000 unemployed Americans to work in the shipyards, and build five new carriers in two months. Neither event has the remotest possibility of occurring because each ignores the real circumstances.