Two extra Dreadnought hulls could alternate strike and deterrent roles

The proposal expands the Dreadnought class from four hulls to six, normally assigning two to conventional strike with removable cruise-missile inserts in their ballistic-missile tubes. A four-boat deterrent force divides between one patrol, one boat available to surge, one deep refit, and one undergoing training or other work. Ageing and unexpected damage make that cycle harder to sustain. If an SSBN needed an unexpected long refit, an SSGN-role boat could have its inserts removed and return to the ballistic-missile force. Six hulls would also provide more capacity to sustain two deterrent patrols when required. The illustrative conventional strike load is 84 Tomahawks if each of twelve tubes takes seven missiles, although the number carried by each insert is recalled with uncertainty. That load would provide a covert opening strike alongside the carrier's sustained air operations. Because design, infrastructure, and training costs are already embedded in the four-boat programme, later hulls should cost less per unit than a simple division of total programme cost suggests.