What separated Renown from Repulse

Both sisters retained high speed and six 15-inch guns, but Renown's comprehensive reconstruction gave her better anti-aircraft weapons, sensors, protection, and operational flexibility. The Admiralty considered sending her east with Prince of Wales but judged her too useful elsewhere, while the less thoroughly updated Repulse joined Force Z. Their energetic manoeuvring under air attack suggests that Repulse's basic hull still possessed valuable speed and gun power. Modernization, rather than age alone, separated an adaptable capital ship from a vulnerable one. A similarly rebuilt Repulse might have offered the Royal Navy another fast, long-ranged ship able to escort carriers and contest German fast battleships. The counterfactual tests investment priorities without claiming that a refit would have guaranteed survival.