at least that's how I made up my mind about this paragraph in the rules in red the phrase I'm referring to...)
If the port belongs to someone else, the owner of
the active galley will have to fight. If the space also contains
galley belonging to the port’s owner, the owner of the active
galley will first have to enter battle with these galleys before
attacking the port (no need to fight the galleys which may
be present in the space which belong to other players. Those
players cannot declare a blockade).
can you confirm it? why is that? to avoid kingmaking?