The building holiday erodes shipyard and armour capacity

MacDonald's personal diplomacy helped define parity and assemble support for continued reductions, but the building holiday also created domestic opposition among shipbuilding unions. Merchant construction could not preserve every skill and production line needed for warships, especially armour and armament capacity. One proposed alternative is a steady, limited replacement program that would maintain fleets, workforces, and industrial readiness without unleashing an unrestricted arms race. An illustrative five-year quota of five ships for Britain or America, three for Japan, and two for France or Italy shows how continuous work might preserve both fleets and specialist skills.