Why War In Pacific Started December 1941

Hello,

I recently came across an interesting theory as to why the Japanese launched the war in December 1941. The usual reason is that because of the oil embargo imposed after the occupation of Indo China the Japanese had to either back down or fight. The new theory is that the Japanese may have decided that war with America was inevitable well before the oil embargo for economic and military reasons.

Military spending in 1941 could have been as high as 49% of the budget with the China war maybe costing $5 million a day. Japan was not earning the hard cash she needed to pay for imports from countries outside the Yen block as the pattern of trade with the Asian mainland was warping her trade balances and by spring 42 they would run out thus triggering a crisis. The only way out was to end the war or seize additional resources.

The Japanese Navy would not be able to compete with the US ship construction programme started after the fall of France but especialy the "Two Ocean Navy" act signed on July 19 1941. Much of the Japanese Navy was in the second half of its service life for example 71 out of 111 destroyers. With much of its Navy nearing obsolecence and no hope of matching new US construction the Navy from about 1943 would always be second to the US navy in the Pacific.

By the end of 1941 the Japanese 1937 Naval construction programme was almost complete. In June 1940 the Navy started a process of refitting and modernisation that would take 18 months and see all its ships bar one destroyer in service at the end of 1941. The Japanese Navy at the end of 1941 enjoyed a superiority it could not long maintain.

It could be a faction in the Japanese military decided to seize Indo China knowing full well the possible consequences indeed it would be strange if the possible reaction of the western powers was not discussed but this western reaction would provide the detonator needed to bring the county together. Japanese strategy often depended on the obvious not being what was realy happening.

The Japanese decided they could not sustain the China war but neither could they stop and admit defeat therefore the only way out was to seize the resources to carry on. If war was inevitable with the US who would assuredly try to stop them it was best to come when the Japanese Navy was at its strongest and because of the US Naval buid up and a looming economic crisis could not be delayed long after 1941 the oil embargo merely brought the war forward.

An interesting theory but it cannot be proved because of the destruction of Japanese documents prior to the US occupation.

 

This is an interesting theory. I wonder if there are any books out there by Japanese historians that would have any supporting eveidence? You make good arguments from both the military and economic points of view. If your observations were not part of the motivation for their actions they seem to be true. War did seem to be ineveitable, they could not out produce the US naval yards, they were in need of additional resources. Good theory.