When the US Navy began its competition for a new generation of surface ships that were small, stealthy and could sail close to enemy shores to deploy special operations forces, the obvious choices to build the boats were Northrop Grumman and General Dynamics, the two big American naval shipbuilding companies.

But by the time the navy announced the two finalists for the $12bn Littoral Combat Ship programme in May, Northrop had already been eliminated from the contest and one of two design contracts went to Lockheed Martin, a company better known for building F-16 fighter planes than battleships.