I always take india J3, with 6 trans, 6 inf, 6 art, and every single plane in in IJA The British have had the opportunity to build a max of 10 inf. With the power of the Japanese airforce, I win every time, and that is before the Aussies can do anything. The US is always occupied taking back London, so there is very litttle they can do other than annoy, they cant do any serious damage.
I feel like a skilled US player would be able to divide his income to be able to take on Japan and take London. 82 IPC’s aren’t necessary to take out the remainder of the German invasion force plus the three units MAX that Germany has built there each turn. If the Germans have done Sealion and fortified London, chances are they’re getting curbstomped by the Soviets. I imagine that the initial neutral builds of the US could take London, in which case they would be free to hit Japan with everything.