They wanted to build a defensive shield against the U.S. and thought it was necessary to cripple America’s Navy to do so.
Given a year and they would have probably done so but we recovered much sooner than they thought we would.
Should have made the third strike. Take out the oil and the dry docks. It would have pushed the fleet back to San Diego and Long Beach.
But missing the carriers made the Japs take their chips and leave the game.
It was a stupid move. The plan worked. They could have encountered acceptable losses in the third wave. It would have pushed the US back two years instead of six months.
They should have called it off after their scouts reported no carriers at Pearl, or waited until they were in port. Imagine if the Yorktown classes ships were destroyed in the same attack.
To a large degree the Japanese had no choice. The Japanese were already allied with the Nazi’s, a war with the US was coming, it was a matter of when. Since war was inevitable, the question then becomes, war on whose terms?
The Japanese leadership decided that it was better to strike decisively early, before the US entered the war in Europe and the US war machine had kicked into high gear.