X-craft as a substitute for weapons Britain did not yet have

This closing argument frames the X-craft as a wartime answer to a problem now often solved by guided munitions. Because the miniature submarine was too small to carry conventional torpedoes, it had to place detachable charges beneath the target. Those charges needed to sink, creating buoyancy and reliability problems that could threaten the attacking craft itself. A modern attack on a stationary, harbor-bound Tirpitz would more likely use cruise missiles. The comparison shows how the Royal Navy improvised a crewed precision-strike system with the technology available during the Second World War.