Britain's choice of the 16-inch/45 reflected status as well as ballistics. American and Japanese capital ships made 16 inches the standard Britain felt obliged to match. A fast F3 with nine 15-inch guns would have been useful overseas, but it would have looked like another companion to Hood rather than the Royal Navy's most powerful ship. Nelson and Rodney instead became the heavily armed ships behind Britain's overseas presence, with nine 16-inch guns making the comparison easy for foreign observers. The treaty ceiling would not support the desired speed, armour, and an unmistakably heavier battery in the same hull. Britain gave up fleet-wide 15-inch commonality to claim visible equality with its two main naval competitors.
Chapter · 28:53-33:45
Why 16-inch prestige defeated the faster F3
Britain accepted a slower battleship because nine 16-inch guns matched American and Japanese prestige and backed Hood's overseas presence with a more heavily armed force at home.