What earlier 4.5-inch guns could have changed

The materials and engineering later used in the Daring-class 4.5-inch system were worth developing before the Second World War. A compact twin mounting that did not penetrate deeply into the hull could have been fitted across several ship types. C- and D-class cruisers might have received rapid dual-purpose conversions, while destroyers could have entered the war with a more capable general-purpose armament. The value would grow when radar arrived because the fleet would already possess guns and mountings able to use improved fire-control information. This counterfactual illustrates that supporting technology must exist before a breakthrough sensor can transform combat performance.