Maybe the message is that in Pearl Harbor, Japan attacked a military installation. In return, the USA killed perhaps a million Japanese citizens en route to occupying Japan. It is not inconceivable that the Japanese would apologize for their attack on Pearl Harbor if the USA were to apologize for attacking and killing a disproportionate number of civilians.

A substantial difference between WWI and WWII was that the atrocities against soldiers (mustard gas for eg) were replaced by (magnified by?) atrocities against civilians.