Why budget alone cannot restore fleet numbers

Why does the US Navy appear unable to increase fleet numbers rapidly?

Its budget is limited, but so is the shipyard capacity needed to turn additional plans into hulls.

Money and productive capacity explain the apparent lack of urgency. Adding smaller combatants still requires yards, skilled labour, suppliers, and construction slots rather than only a larger headline budget. The same constraint makes casual proposals to build Australian submarines in already loaded American yards implausible. Naval force structure remains bounded by the industrial base that must physically deliver it.