Builds
B1: 1 IC, 2 Bombers
B2: 1 Carrier, 1 Battleship, 1 Transport
B3: ???
A1: 1 Carrier, 1 Bomber, 2 Transports
A2: 4 Bombers
A3: 4 Bombers
The total cost for the air/sea/transport/IC force, including starting units, is about 347 IPCs
The total cost of the starting Japanese Fleet is about 207 IPCs, plus about 100 IPCs worth of units built on turns 1 through 3.
My analysis is that Japan could certainly disrupt aspects of their move (taking out the Russian Ground stack or the Indian Fleet), but doing so would leave them fatally vulnerable to other aspects(whichever they didn’t take out, the American Fleet, and the American Bombers). More importantly, they won’t realize the full extent of what is happening until after J2, and any units built on J2 or J3 would be unable to reach the allied fleet anyway. Until after J2, it simply looks like America is building up a Fleet, Britain is going for an IC in India, and Russia is being aggressive. Unless Japan does everything right, they could easily be screwed. Even if they do plan properly, the situation is going to be a dicey one.