Europe has written down what a deployable underwater-intervention capability should be, and it has written it down well. The specification calls for containerised mission modules of standard size, movable by land, air and sea, carrying diving and unmanned underwater equipment, operated by qualified people, arranged around an open architecture so that the package can be tailored to the mission rather than rebuilt for it. The description is precise enough to be costed and procured. It is also, on its own, inert. A module does not hold an authorisation; a certificate is issued to an organisation and can be withdrawn from it. A qualification is not a competence, and neither is a medical fitness. A chamber standing in a yard is not an assured route to recompression. A container that fits inside an aircraft has not thereby been flown. Each of these is a separate state of affairs, each is held by a different party, and each decays at its own rate unless something obliges someone to keep it current. The interesting question is therefore not whether European industry can build the equipment, but what has to be true at the same moment before the equipment counts as a capability that can be called out.