The proposed force buys eight Vanguard-class hulls rather than the historical minimum. Four remain SSBNs, while four carry conventional cruise missiles as SSGNs, allowing one of each type to stay at sea. Common hulls would also create resilience because an SSGN could be converted back if an SSBN were lost or badly damaged. The conventionally armed boats could deploy near an ally or provide a survivable response after an attack disabled other British forces. The example shows how class size and commonality can buy strategic options beyond the primary nuclear mission.
Notable Point · 49:25-50:45
An eight-boat Vanguard SSBN and SSGN force
Four ballistic-missile and four cruise-missile Vanguards would preserve both nuclear and conventional submarine responses.