Is it an unprovoked declaration of war if Japan attacks UK forces in Yunnan (Chi

[Admiral De Ruyter]

Is it an unprovoked declaration of war if Japan attacks UK forces in Yunnan (China)? 

[Piet Hein]

Second Question (alpha2):
If Japan attacks UK or ANZAC before US3, does that allow US to declare war on Germany in its next collect income phase?

[Hobbes]

Is it an unprovoked declaration of war if Japan attacks UK forces in Yunnan (China)? 

If the UK moves forces into China then it is the same as declaring war on Japan. Thus, Japan may attack those UK forces in Yunnan free of consequences (i.e. the US declaring war on it)

[Admiral De Ruyter]

Thanks Hobbes!

[Krieghund]

Second Question (alpha2):
If Japan attacks UK or ANZAC before US3, does that allow US to declare war on Germany in its next collect income phase?

No, if Japan attacks UK or ANZAC (assuming UK/ANZAC didn't start it), that allows US to declare war on Germany (all Axis powers, actually) in its next Combat Move phase.

[Piet Hein]

Ok thanks alot.
So just for my understanding:  without any Japanese DOW to UK, ANZAC or US, the US may declare war in the collect income phase of US3.
With such a declaration, or if London/a North American territory is captured, the US may declare war on the combat move phase of the US turn following a Japanese DOW.
And an attack on Russia by any of  Japan/Germany/italy does not influence the US DOW right ?

[ghr2]

US can DOW on the axis after Londong falls?
After US declares war collect income turn 3, it gets the bonus income from the NOs right?

[knp7765]

US can DOW on the axis after Londong falls?
After US declares war collect income turn 3, it gets the bonus income from the NOs right?

Yes, the US can declare war on any or all Axis if London or any territory in North America is captured.  This is in the Alpha+2 rules, not OOB.
Yes, assuming the US hasn't been brought into the war before round 3, they can declare war on any or all Axis on the collect income phase and immediately goes to a war footing which enables all the US national objectives.

Ok thanks alot.
So just for my understanding:  without any Japanese DOW to UK, ANZAC or US, the US may declare war in the collect income phase of US3.
With such a declaration, or if London/a North American territory is captured, the US may declare war on the combat move phase of the US turn following a Japanese DOW.
And an attack on Russia by any of  Japan/Germany/italy does not influence the US DOW right ?

Yes.
Yes.
Correct.  Any action against Russia does not affect the US and visa versa.