Yes, it would have to be dependant upon how strong the air defenses of the base were. The only thing is that Paradox would have to come up with an entirely new rule set to determine how 'port attacks' would work, and that would take up valuable time that could be dedicated to the AI, or something else equally important.
All thing said, I don't think we'll see port attacks in any version of HOI. Hopefully I'll be wrong, but hopefully not at the cost of something more important.
All thing said, I don't think we'll see port attacks in any version of HOI. Hopefully I'll be wrong, but hopefully not at the cost of something more important.