Well Australia would undoubtely be a case of : " Great we have it, now what" so it would technically open a "second front". The Diversion in the Aleutians would also be a genie they could not get back into the bottle that would result in yet another front opening up. I don't think Japan had enough resources, in their wettist dreams, to fight a battle on so many fronts considering they had their hands full with China and the Pacific.

Just my humble two cents worth.

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"Logos, Philos, Arete"