Two buddies and I have played about a dozen games, and it seems to get easier and easier to contain Japan. First, you don’t have to control all of the DEI, you just need to prevent Japan from controlling them. With all of Asia under control (except India), the Phillipines, and three out of the four DEI islands Japan is only at an economy of 61. Not much better then the US, except they have to buy alot more ground forces and likely more transports. While the US is devoting themselves almost soley to air and navy, and has two to three minor allies that add to Japans troubles.
We usually find the Japanese fleet operating in the south, and so with no real threat to Hawaii the US fleet will base itself in Australia (frequently the Aussies will build an airfield in the Northern Territories) and move air units down there as well waiting for the Japanese to split up or pick off transports. If Japan doesn’t opt for a J1 attack the Brits can land four infantry, four fighters and a tac bomber on Java, the Anzacs can augment this with four more fighters. This presents a threat to all the other DEI islands, plus the threat of massing US units in the area. If Japan does manage to gather enough units to threaten java the air units can just rebase to India or Australia. We’ve had Japan counter by landing fighters in the Phillipines, but then you no longer have a mass of fighters guarding the homeland, so US builds moving thru Hawaii are routinely a threat. Both sides use blocking destroyers, but, both sides usually go out of their way to kill these too.
All too many times we find the Japanese presented with a choice of assaulting multiple targets, but, if Japan does they’ll have to either sacrifice their transports or split their fleet and face an allied counterattack. Meanwhile India is just digging in and fighters from the US and Anzac are only a turn away from defending Calcutta. Japan got an advantage in our early games, but, the allies have been on a roll as of late, giving them a slight edge on games won. I don’t think Japan has to do anything wrong for the allies to win, I just think that unless Japan can gain control of all the DEI (and thus gain their NO bonus) and hold it, they are pretty much on a timer until they’re whittled down by the allies.