Ballistic-missile submarines are the Royal Navy's most powerful assets, but deterrence rather than combat is their daily mission. Continuous at-sea deployment keeps one boat ready at all times so an opponent cannot eliminate the retaliatory capability in a first strike. The weapons are intended to establish a ceiling against nuclear attack or an existential assault on British sovereign territory and allies. Their value therefore comes from credible availability and the expectation of response, not routine use of their firepower.
Notable Point · 1:02:29-1:03:58
Why deterrent submarines are continuously deployed
Britain's ballistic-missile submarines are most powerful when never fired because continuous deployment establishes a ceiling against existential attack.