Yesterday evening, the UK government voted to retain the country's Trident nuclear deterrent. Since 1969, the United Kingdom has had a Continuous At Sea Deterrence (CASD) tasked with protecting the nation in the case of a nuclear attack
. 1 submarine is constantly armed and at sea while another is undergoing maintenance. A further 2 are in port or training. The submarines around which the system is based are due to be replaced and that could cost an estimated £31 billion. Read the full story in the Independent where the following infographic was featured.