I've lost money in Tortuga, so it is capturable for the NPCs too.
May be we need to take a look into the code?
Cheers.
buho (A).
I also have lost money in Tortuga, and in Willemstadt, as in L'Havana and in Port Royal.
This means that all cities, also capitol ciities, may be sacked (
except for Panama, pillaging only in the Pirate's quest-line).
This is expected in the game Vanilla.
The incertitude is if they can be captured.
Certainly, L'Havana and Port Royal can be captured.
If doubts remain, i load old savegames and try to capture also of Tortuga and Willemstadt.
However, for Tortuga there are no impediments, but for Willemstadt there are obligations connected with other quests (quest-line pirate's, quest of beggars, quest-line English, French, Spanish, Dutch, and probably others who do not remember).
Perhaps, because of this, Willemstadt is blocked and must remain always Dutch: can be sacked, but no captured.