A couple of interesting observations

[EarlyDoors]

After Japan DoW on USA Germany is not at war with USA, however there seems to have been a recent change that allows US units into Allied territory. Once in that territory those units can attack and be destroyed by German units Without a DoW.

Also if a major upgrades the air defences of a minor which subsequently surrenders, then those defences are reset to zero even if the resource / town is occupied and remains under the majors control.

[BillRunacre]

Regarding the first situation, that is normal, as a fully mobilized Major can enter the territory of other friendly countries, and fight in their defense, however their units cannot move into an enemy country without being at war with the relevant Major.

[FOARP]

The first situation makes sense as the alternatives are:

- Preventing US units entering allied territory, which would prevent them doing anything against Japan.

- Preventing US units from being attacked when on allied territory and not at war with the attackers, which means they could simply block attackers.

Also the second situation makes sense, as the defenders from the minor manning the air-defences will have deserted.