Its not so much the economy of the US, because generally when I play Japan I have at least a round or two of 50+ IPC to spend and my fleet is superior to the US fleet provided I keep the fleet combined or able to pounce. Problem occurs in dealing with 8-10 subs hitting Hawaii and then heading straight for Japan.
It basically forces my fleets to all move to SZ6 to prevent 16-20 die rolls just from subs for 3 to take out Japan’s IPC value and placement of more ships as well.
You just can’t place enough ships in a single round to take out all the subs there, especially with a US fleet sitting on top of it.
I am supposing the only real choice is to hit the stack of US subs when they are on the defensive side and rolling at 1’s instead of 2’s. That means when they land in Hawaii as that is the gateway to the Pacific for the US.
As an aside, I do have a question regarding SBR and Air Bases: We had a discussion about if you can SBR the AB to prevent a scramble from that AB in the same turn you SBR in. We came to the conclusion that you declare all your combat moves, declare scramble then conduct SBR which negates that move.