Why doesn’t Japan simply ignore Guam and the US forces there and use all of its fleet to sink the US fleet at Wake on J2?
The US has 1 AC, 1 BB, 1 CA, 1 DD, 1 SS, 1 FTRs and 1 TAC, plus 3 FTR (including the ANZAC one) and 2 TAC that can be scrambled). Japan should be able to bring at least 2 ACs, 2 BBs, 1 CA, 2 DDs, 1 SS, 2 FTRs and 2 TAC (all of them starting in Japan/Carolines), plus any planes stationed on the Carolines (they can land on the Marshalls afterwards) and any bombers in Japan/Carolines.
Afterwards on US2, the US player will still have Guam but its 3 bombers and 1 fighter aren’t enough to hit SZ6 since Japan can scramble planes to deal with the attackers.
And for Japan it is a great deal since they send the initial US fleet to the Pacific bottom without risking losing its own against counterattacks. The US will need to rebuild its fleet from scratch.