Tsushima made battle-line cohesion the prewar lesson

World War I and early postwar thinking still relied on a line of battle, unlike the task-force system familiar from World War II. A widely drawn lesson from Tsushima was that the cohesive Japanese formation could coordinate long-range fire and overwhelm the Russian fleet. Twenty-one knots therefore remained acceptable when every ship needed to hold its place in the same battle line. The Queen Elizabeths formed a faster line that could counter German battlecruisers trying to turn the British formation while still meeting them with battleship armour and 15-inch fire. Speed had a different tactical meaning before fleets became small task groups.