Rebuilding merchant shipping after the First World War

How could Britain rebuild its merchant marine efficiently after the First World War?

Use five-year tax incentives for British-built turbine ships and refits, add wartime fittings, and seek faster merchantmen while expanding machinery and weapons capacity.

The imagined 1920 programme pairs each new turbine-powered merchant ship with reconditioning of a triple-expansion ship. Tax relief could be spread against profits over five years, provided the work took place in British yards. Further incentives would provide weapon hardpoints, ammunition storage and accommodation for wartime gun crews on ships using critical routes. Torpedoes are proposed to make surface raiders keep their distance. The scheme also aims to expand turbine, boiler and weapons production before wartime demand arrives. A target cruising speed of 18 knots would let convoys cross the Atlantic faster and complicate submarine interception.