Then, in 1980, the Thatcher Government purchased the new "Trident" missile system from the US to replace Chevaline and this was finalised in 1996. Submarines carrying Trident nuclear warheads are based at HMNB Clyde and the Scottish National Party affirmed that it would remove the submarines if independence was gained following the 2014 referendum. While experts suggested that the submarines could be relocated to a Devonport base in the English city of Plymouth, the Scottish CND advocates for the complete abolishment of the Trident warheads.