https://www.youtube.com/watch?v=tfJ0pN_x3sc

Once the new submarine class comes fully online, they’ll replace London’s current ballistic missile submarines. The Dreadnought-class of submarines will replace the United Kingdom’s Vanguard-class submarines which currently provide the Royal Navy’s silent underwater nuclear deterrent. Though certainly among the world’s most capable nuclear submarines, the Vanguards have been in service with the Royal Navy since the 1990s, making the oldest of the submarines nearly thirty years old. Former Defense Secretary Michael Fallon stated that the Royal Navy “cannot know what dangers we might face in the 2030s, 2040s and 2050s,” justifying the submarine’s construction.