Alrighty then.
The second Sino-Japanese war was a result of secret meetings between Chiang Kai-shek and FDR. FDR convinced the Chinese leader to occupy Japan's attention with war while he filled the power void in SE Asian countries as a result of the French and English losing their imperialistic stronghold. FDR promised to share the wealth of control over the vast amount of natural resources gained by the new found US influence in Vietnam, Thailand, Cambodia, and Laos. It was a brutal loss for China but the long term payout was insane. It almost worked. On the other side of the World, France was begging the US to get involved in Europe. FDR had no reason to. Not only did it do nothing to advance US imperialism, it was incredibly unpopular among the American populace. France knew about the past negotiations between Chiang Kai-shek and FDR and threatened to tell Japan if FDR didn't save them from the Germans. FDR refused because he knew getting involved in Europe would insure he didn't get re-elected. France told Japan, Japan attacked Pearl Harbor in retaliation for FDR convincing China to wage war with them. FDR used the attack on Pearl Harbor to gain the popularity of declaring war, but he chose Europe as his starting point to appease the French so they wouldn't tell the rest of his secrets.