66. The public debate over the future of the UK's strategic nuclear deterrent should address:

• the independence of the UK's current system; and
• the operational and diplomatic impact of any potential dependency on the United States of any future UK nuclear deterrent.

67. We heard a range of conflicting opinions about the degree to which the UK's current strategic nuclear deterrent represented an independent system.

Potential dependencies on the United States

68. Some witnesses to our inquiry questioned whether the UK's nuclear deterrent was genuinely independent. Witnesses pointed to a range of technical and operational dependencies of the UK's Trident system upon the United States and suggested that such dependencies fundamentally detracted from the UK's independence at a international political and diplomatic level.

69. The warhead: Greenpeace told us that the UK warhead fitted to the Trident II D5 missile is a direct copy of the US W76 warhead; that the arming, fusing and firing system used by the UK was designed by the US Sandia Laboratory and was "almost certainly procured from the USA"; that the neutron generator used on UK warheads was manufactured in the USA and was acquired "off the shelf"; and that the re-entry body shell, which contains the warhead, was purchased by the UK from the United States.[57]

70. The missile: Dan Plesch, of the School of Oriental and African Studies, told us that the Trident II D5 missile was designed and manufactured entirely in the United States; that the UK did not own its Trident missiles in any meaningful sense, that they were, in effect, leased from the United States and held in a communal pool at the US Strategic Weapons facility and were not identifiably British; that servicing of the missiles was conducted exclusively by the United States at King's Bay, Georgia; and that the Mark 6 guidance system used on the UK's Trident missiles was designed and made in the United States by Charles Stark Draper Laboratories.[58]

71. The platform: Dominick Jenkins, of Greenpeace, told us that although the UK's Vanguard-class SSBN submarines were designed and built in the UK, many aspects of the design "are copied from US submarines and many components are bought from the USA"; that in order to assure the accuracy of the missiles, the exact position of the UK's submarines had to be precisely determined, that this was achieved by relying on two US-systems, GPS and ESGN, and that the US "has the ability to deny access to GPS at any time, rendering that form of navigation and targeting useless if the UK were to launch without US approval"; that targeting software was based upon US designs, that weather and geodetic data, which help ensure the accuracy of the missile, was supplied by the US Navy, and that "all the hardware and software used by the [fire control] system is US-produced", with the hardware manufactured by General Dynamics Defense Systems.[59]

72. The onshore and warhead infrastructure: Dan Plesch told us that Devonport dockyard, which serviced and repaired the UK's Vanguard-class submarines, was managed by DML, a consortium which was part owned by the US firm Halliburton, and that the Atomic Weapons Establishment at Aldermaston was managed by a consortium part owned by the US firm Lockheed Martin.[60] He also claimed that the A-90 plant used at the Atomic Weapons Establishment (AWE), Aldermaston, to manufacture warheads was a direct copy of the T-55 plutonium processing plant at Los Alamos and that the UK used the US nuclear testing si

We call upon the MOD to clarify the technical dependencies of the UK's Trident system upon the United States and to respond to the argument that the UK's nuclear deterrent is not truly independent. In weighing the importance of maintaining independence, attention needs to be paid to the differing concepts of independence adopted by the UK and France. (Paragraph 84)