Destroyer question: Can they carry infantry in AAP40?

Other than the UK/ANZAC ability to take control of them peacefully, they are treated as territories whose capital is in enemy hands.  Whoever captures them from Japan will have control of them.

Yes it can it ignore it and bombard

You seem to have it all correct. Your planes can not hit the subs because you do not have a destroyer in the battle. Japan may not remove them as a casualty, if you hit with your planes.

The Japanese subs also don’t get to shoot, if all you have fighting in the naval portion of this attack are planes.

Ok, that makes sense.  Sorry for the dumb question. :-P

The UK and ANZAC are free to move any units into Dutch territories still under Dutch control at any time, but they may only take control of them with land units.  The US is free to move any units into Dutch territories still under Dutch control only if it is at war, and it may never take control of them.  Any power may attack Japanese-controlled Dutch territories and take control of them, as long as that power is at war with Japan.

yep. every round.

@Veqryn:

question 1) can you take an empty territory with a single tank, then move 10 mech infantry through it to attack the enemy territory beyond it all during the combat phase?

No.

@Veqryn:

question 2) can you take an empty territory with say, 3 tanks and 3 mech infantry, move through it and attack the enemy territory beyond it, win that battle, then during the non-combat move, back up that territory by moving 10 mech infantry there through the now conquered enemy territories?

Yes.