The NHS had roots before the Second World War

Would Britain have failed to create the NHS if naval treaties had not halted capital-ship construction?

No. Earlier welfare reform, civil-defence needs, and existing local medical systems had already placed universal provision on a longer path.

Continued capital-ship construction would not by itself have prevented Britain's National Health Service. Welfare legislation and movement toward broader medical provision predated the Second World War. Interwar fear of mass bombing gave the state a national-security reason to expand the pool of doctors, nurses, and other medical personnel before a future Blitz. Policymakers considered several structures, including central control and national health insurance, rather than moving directly toward one inevitable model. Local and community health systems, including examples in Wales, supplied organisations and practices that the national service could absorb. The later use of trusts reflects that inherited institutional variety rather than a system designed entirely from a blank page. These developments give the reform a longer prehistory than a single post-war creation story suggests.