Why did prewar capital ships take about two years to build while smaller modern warships take much longer?
Short answerModern ships are more complex systems-integration projects and are built by a much smaller supporting industrial base.
NotesWarship construction time depends on the size of the supporting industrial base as well as the complexity of the ship. Modern systems must work together, and integrating them can take much longer than assembling the hull. One procurement criticism is that rival contractors prefer customers to remain dependent on their proprietary equipment. Meeting the exact wording of a contract does not necessarily make different suppliers' systems easy to integrate. Governments also pay for slower construction to preserve shipbuilding capacity between orders. That policy keeps work available but extends the time required to deliver individual ships.