The Power to Close the Sea
Rome, Carthage, and the Strait at the Origin of Maritime Hegemony
Maritime power is never decided on the open sea. The horizon cannot be held, blockaded, or taxed; what can be held are the places where the sea narrows to a line — the straits and passages through which the traffic of whole basins must funnel. It is there, not on open water, that the fate of every thalassocracy is settled, because it is there that a single power on the shore can do the one thing the open sea forbids: it can close. The history of sea empires is, in this sense, a history of chokepoints — of who holds the doors, and of what follows when a door changes hands. Carthage, the foremost naval power of the ancient West, learned this in the hardest way, for the beginning of its long road to destruction was not a defeat in open water but the loss of control over a strait: the narrows between Italy and Sicily, where the First Punic War began. From the moment Rome forced that passage, the governing question of the centuries that followed was no longer whether Carthage might defeat Rome, but whether any power other than Rome would keep the capacity to close the sea. This essay pursues that question from the strait at which it opened to the imperial peace it made possible — and to the moment, six centuries on, when the power to close slipped back into many hands and the sea ceased to be one.