RESURGAM project aims a decisive break-through with Friction Stir Welding (FSW) as a high integrity, low distortion, environmentally benign, welding technique to be developed in steel, in air, to facilitate the modular construction of ships across multiple yards with final assembly at one master yard and the development of the process of underwater, robotic FSW to allow repairs to be carried out on marine structures without needing to bring ships or platforms ashore to a dry dock. These fabrication and repair capabilities, backed by the secure, digital Industry 4.0 infrastructure and techniques already in widespread use in the automotive and aerospace industries, will facilitate the rapid, coordinated but distributed modular manufacture of ships and watercraft throughout Europe. Practically, this will allow ships damaged anywhere in the world will have the option of being repaired in place without the need to travel to the nearest dry dock. All of this will be implemented by the European shipyards and Naval architects in Europe.