How British will our "deterrent" be?

This is a schematic illustration of an Astute-class submarine, on which the Successor-class will be based. These vessels are planned to carry the Trident-II nuclear ballistic missile commissioned by the Conservative government. Although the boats will be built in England (largely from French steel, as the Daily Mail, quoting the Mirror, has pointed out), practically all the equipment will be foreign. (The basic illustration is from The Submariners Lounge; I am indebted to Private Eye magazine for the detail indicated by the yellow arrows.)

The Eye adds that should "any of this foreign technology go wrong, the subs will have to be lifted out of the water for complex maintenance. There is a huge crane at their base in Faslane designed to do exactly that. The Shiplift, which cost £314m [...] was built by Jacobs Engineering, based in Dallas, Texas."