A recurring problem in AoD (and HoI2) is that the US, despite being a superior nation is very incompetent in waging war against Japan: Unprotected transportships, stacking armies in the Marshalls, no co-op with allies etc etc.
Is there any way to make USA more competent to fight?
good question - once US has an idea, what it wants, it's quite persistent.
I (Japan '36 campaign) fought for new guinea for about 6 month in 1944 against 23 divisions of the US!
in the big picture, this wasn't the best strategy for them because i managed to capture the whole of Australia in the meantime...and india in the west.
I guess I would have had more trouble if they just forgot their stupid offensive of worthless new guinea an had helped their allies!
my experience of 3 games as japan was:
US ist quite a pain in central pacific, invasions to capture kwajalein, truk, yap,... and as mentioned new guinea, but they don't use these capured bases to put fleets there to disrupt japanese lines of supply/ressources/troop movement. So a bit of a tweak in AI could improve the US warfare quite a bit.