Question: When italy joins axis - is that a declaration of war?

Yes.

The rules state that Germany can build an IC on axis minors that qualify. Can Germany build the IC on the turn they activate the minor or do you have to activate and then build the IC on the next turn?

If the subs fire in the First Strike phase they are detected for that round of combat.

The planes would fire on the subs once and then in the second round the surviving subs could submerge.

Yes, and no.

The limit is one… and all parties can do it.

Of course it doesn’t help when the russians drop that in Moscow with a stack of 70+ units.  But, if Germany can do the same? What does it matter.

Bump for update 5.1 rules:
Damaged Battleships attack & def at 5 or less

It should be the same for Nat China. Szechwan falls, China can’t build no more whether they have 3 or more territories worth 3 icp’s or more.
If it’s liberated then they will get 6 icp’s and any non captured territories and can start building again.

If they have some money left and Szechwan is captured, they should have to give money to attacker. I would like to try this in a game.

The rule is as long as they have territories worth total of 3 icp’s or more, they can build and place in those territories.

If Germany invades the Baltic States or East Poland, Russia will consider this as an act of war. Russia is moved up to its full production and is at war with Germany.

I think if Denmark is neutral then the straights should be open to any country. Germany should take Denmark to keep the UK fleet from entering….I will add this in my 6.1 rules coming out this weekend.