Continuous shipbuilding preserves skills and controls cost

Have the Royal Navy and US Navy fallen behind a common NATO warship standard?

Not in any simple sense. National requirements differ, while continuous shipbuilding is a stronger predictor of affordable, capable designs than a single NATO baseline.

European warship design has no single standard because national requirements and industrial habits differ. Italy, Japan, South Korea, China, and the United States retain design and production experience through steadier ordering. Navies that repeatedly stop and restart construction lose continuity, making later ships more expensive and complicated. Fleet quality therefore depends on the production system behind a design as well as its advertised weapons.