The US is not going to sit on its hands whilst the Nazis take over Europe and the Japanese take control of the Pacific. They were isolationist, not stupid. They will eventually declare war on the Axis and go to total war, except not with the same resolve as they had after Pearl. Japan knew this and thats why they attacked the US preemptive.
I tend to agree with you but the US is NOT a dictatorship where the politicians get to make all decisions. IF there's no Pearl Harbor and the Japanese can avoid any further stepping on their dicks (IE the rape of Nanking) where the world turns against them for their behavior, I think it could be exceedingly difficult for the US to go to war with them. The American public did not see Japan gobbling up the Dutch East Indies, Borneo, Malay or the any of the French colonies as something that would directly harm them. They looked at that situation as the European Colonialism and were in no mood to waste American boys propping up the old 'Status Quo' for them.
I think had Roosevelt maneuvered the US into a war without the PH event there would have been hell to pay. He had promised the American people he was 'not going to send American boys oversees to fight other peoples wars'. If he in fact did that in 41 right after the election I think there would have been impeachment hearings. The US government would have been in chaos.
I have contended for many years that had Japan not attacked the US and went solely against the Allies possessions these things may have happened;
- By finishing the war with China Japan would have had 30 to 35 divisions to use.
- Those divisions could have been used to quickly overrun Burma and invade into India
- Invading into India would most likely have been the straw that allowed Rommel to capture Suez and potentially link up with the Japanese in India.
- At that point the Axis would have had more then enough oil to fuel their armies
- By kicking the British out of the Med that would have made Italy a stronger partner as they no longer had to defend a gazillion miles of coastline
This possibly could have all happened during the year of 41. By 42 how are you going to explain to the American people that we have to go to war to re-install the British, French and Dutch over the Germans, Italians and Japanese when it comes to managing overseas colonies. I don't think they buy it.
People weren't as sophisticated back then and had very little sense of globalism. They viewed things in much simpler terms then we do today. The US was safe because we had oceans separating us from all the bad shit happening elsewhere that wasn't our business.