@Trisdin:
I am seriously considering attacking all the reachable US ships on J1. If I don’t, I feel I will be giving the US time (to build up) money (NOs) and position (consolidated fleet).
Be careful attacking America too early in the Global game. Granted, the earlier that Japan attacks the greater the advantage that they have against the Pacific allies; however, an early attack not only bring America into the war against Japan, but against Germany/ Italy as well.
A J1 attack would allow America to start invading Africa on US2, and start pushing into the med on US3 and 4… this would be devastating for the Axis in Europe. Germany and especially Italy need as much time as possible to make early gains against Russia/ Africa respectively. If the US is allowed to enter that early, Russia should have no trouble holding back the Germans and it will be a quick game for the Axis.
In my group’s Global games, the best thing that the Japanese can do is force the US to devote its resources into the Pacific theater rather than the European. If Japan can put pressure on the US and force it to take its eye of Europe, this will give Germany and Italy the time they need to topple Russia. For that reason, I suggest attacking on J3 (at the earliest) or J4 to give your allies time to do their thing. If you are playing a straight Pacific 1940, I see no reason not to attack on J1 or J2.