User blog comment:NovaSims/What WW2 have been like if Hitler adnt attacked Russia and Japan hadnt attacked America?/@comment-4206034-20120916150809/@comment-32656-20120918081715

Soviets have a major numbers advantage in soldiers. They also actually had more industry, and in many cases better equipment. Tactics were their problem, at least to start. Germans wouldn't push them back.

Americans would have intervened long before that, Imp. They invade any colonies, and you have US intervention. And the Japanese knew that. Hence, Pearl.

Yamamoto actually knew that long before Pearl. He may have planned it, but he also argued that the concept was sheer stupidity.