The war was inevitable as Japan was running out of the fuel required to support it war in China, let alone a war of agression throughout the Pacific.

The reason that Dec 1941 was selected as the date for the ainvasion was that Japan’s logisticians calculated that by that date there would remain enough fuel to support a rapid advance to the East Indies oil fields, and supply the IJ military while the East Indies fields were brought back on line.

The timing was driven by the fuel situation.

As for not attacking the US, there was no way the Imperial Japanese General Staff was going to go to war with their left flank left exposed. Any drive to the East Indies would require the Phillipines to be neutralised in the opening moves, otherwise it would provide a base for the US military to build up and menace Japan’s oil pipeline to the home islands.

There was never any real liklihood of the US and Japan not going to war, the Japanese saw only two options one the oil embargo cut in, capitulation or conflict.

Given the mindset of the Japanese military of the time, conflict was the only option.

Unicorn