Originally Posted by Rochard

It's been said that the man who planned the attack on Pear Harbor (Isoroku Yamamoto) said ""I fear all we have done is to awaken a sleeping giant and fill him with a terrible resolve." If he did say this or something similar, it was very true. Japan completely underestimated the Untied States in all areas, including manpower, resolve, and material and manufacturing - We could physically build ships as fast they could sink them and we had nearly unlimited resources.

Germany did the same with Russia - Russia was huge and vast, and had unlimited manpower.

Attacking Pearl Harbor was the biggest military mistake of all time.