Deterrent submarines depend on continuous yard skills

Are Ohio- and Vanguard-class ballistic-missile submarines still viable deterrents?

Yes, but upgrades cannot remove the industrial risk created when replacement construction is too intermittent to preserve skilled labor.

Ohio and Vanguard remain viable deterrents in this assessment, with different approaches to preserving capability. A large American production run allows later flights to differ substantially from the first boats, while Britain's smaller force relies more heavily on midlife upgrades. Vanguard replacement was delayed in part by problems inherited from the Astute construction programme. Too little work had passed through the yard to retain enough trained people, so rebuilding the workforce became part of the production task. Continuous orders can sustain those skills in a private yard. A proposed alternative is a Royal Dockyard able to retain and train workers through gaps without having to justify that cost through current commercial orders.