Would holding Zeelandic Flanders (Zeeuws Vlaanderen) be enough to be able to keep Antwerpen open? It would imply a Spanish-Southern Netherlands naval presence, which can keep Zeelandic raiders at bay, though for that to be possible they must be able to defeat the navy of Zeeland. Zeelandic Flanders, North Brabant and Dutch Limbur, especially at this point, would not be harder to hold by the Spanish than the rest of the Southern Netherlands. It would mean a blow to the house of Orange-Nassau, their original core possession in the Low Countries was the Barony ((High) Lordship) of Breda in North Brabant (the marriage of Johanna of Polanen, heiress of Breda, with count Engelbrecht of Nassau-Dillenburg brought the house of Nassau to the Low Countries).