How practical is it to build a cruise-missile submarine that cannot be distinguished from a ballistic-missile submarine without measuring its hatches?
Short answerOhio conversions demonstrate the basic approach. The British possibilities mentioned are Vanguard conversions or additional Dreadnought hulls, both described as proposals.
NotesOhio-class conversions provide an existing example of cruise-missile submarines sharing their basic hull with ballistic-missile boats. A British conversion proposal is described as using missile-compartment inserts in Vanguard-class submarines with remaining hull life. That remaining life is qualified by the suggestion that the boats would need to be used gently. Clarke prefers additional Dreadnought-class construction and describes that alternative as another option raised in discussions. Neither British option is presented as an adopted programme.