Why intermittent British warship building costs more

Are British warships economically unsustainable compared with foreign designs?

Not inherently; low production volume means the state either supports commercial work, pays to retain yard capacity, or builds enough ships to sustain continuous production.

Ship price differs from the industrial cost of keeping a yard and skilled workforce available between naval orders. Small, intermittent programmes force the state to support commercial work, pay explicitly for retained capacity, or accept higher unit costs. Headline pre-war profit margins cannot be applied mechanically to wartime construction, when overtime and accelerated production changed the cost base. Lucrative foreign contracts also differed from Admiralty orders scrutinised by directors of naval construction and Third Sea Lords who understood the work being priced. Cartel behaviour remained a concern, though wartime oversight and the threat of profiteering action constrained what yards could charge.