Stockade

The Stockade has no weapon mounts. This is not an oversight the Fleet plans to correct. It is a slab of plating wrapped around enough reinforcement to keep that plating in one piece, and its only job is to stand where the enemy is shooting and keep standing. The doctrine writes itself: put the Stockade between the guns and the gunships, and let the enemy spend its volleys cracking armor that does not shoot back instead of killing the hulls that do. Every salvo the Stockade soaks is a salvo the warships behind it never feel, and that bargain — a dumb wall traded for a working battle line — is one the Fleet makes gladly. Crews assigned to it learn to take a particular pride in the arithmetic: the Stockade cannot win a fight, but it can decide one, simply by being the wrong thing to shoot at the right time. It will not kill you. It will make sure the ship that does kill you lives long enough to.