Speed and the capital-ship spectrum

The Fifth Battle Squadron's speed problem becomes the starting point for a broader explanation of capital-ship roles. A projected twenty-eight-knot Queen Elizabeth would have combined contemporary battleship protection with enough speed to catch early battlecruisers, which helps explain the demand for thirty-two- or thirty-three-knot ships such as Renown and Repulse. British battlecruisers sit toward the cruiser end of the spectrum because their survival depends on retaining a speed advantage over battleships they are not designed to fight on equal terms. German battlecruisers carry more protection because they are expected to support an outnumbered battle line and survive battleship fire long enough for German battleships to prevail elsewhere. Fast battleships occupy the middle by accepting some tradeoffs in maximum armor or firepower to gain operational speed. The discussion shows why labels alone are less useful than asking what a ship must catch, escape, or support.