House of Commons - Defence

Select Committee on Defence Eighth Report

4 The independence of the UK's Strategic Nuclear Deterrent

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 site in the Nevada desert for sub-critical nuclear tests to ensure that the system continued to work effectively.[61]

73. Some of our witnesses felt that such technical dependencies upon the United States compromised the UK's independence of policy and diplomatic decision-making and that, as a consequence, several of the UK's continental allies regard the UK as "a vassal state".[62]

74. Dan Plesch argued that the current US-sourced Trident system failed what might be termed "the 1940 requirement" (an ability to be used in situations of extreme national emergency when the UK was alone and isolated) and that the UK would, in practice, not be able to use its nuclear deterrent in circumstances in which the US was either neutral or actively opposed to UK policy, or where the US was an adversary. Mr Plesch asserted that although such circumstances are highly unlikely "this is precisely the test that an independent force must pass to be worth the expenditure of financial and political capital". He also stated that "any US sourced successor to Trident will be subject to similar dependence".[63]

75. Professor Colin Gray accepted the UK's dependence on the United States, but claimed that he was not concerned by it:

Operational independence

76. Other witnesses took the view that, in an operational sense, the UK's nuclear deterrent is independent.

77. The warhead: Commodore Tim Hare, a former Director of Nuclear Policy at the MoD, told us that although the US had long shared its warhead designs with the UK, and that the British warhead closely resembled the American W76 design, the UK retained the design authority on its Trident warhead. Commodore Hare also told us that whilst AWE Aldermaston was managed by a consortium which included Lockheed Martin, it was nevertheless owned by the MoD.[65]

78. The missile: Dr Lee Willett, of RUSI, stated that the Trident II D5 missile was "a totally self-contained package" which had "an inertial guidance system that takes it to a point in space, and then the ballistic trajectory then takes it to the latitudinal and longitudinal point on the target" and that "[i]t does not…. rely on external guidance systems such as American satellites".[66]

79. The platform: We heard that the Vanguard-class submarines were designed and built entirely in the UK and that the UK retained design authority on the boats.

80. It is important to distinguish between two different types of independence: independence of acquisition and independence of operation. We heard that independence of acquisition is what the French have opted for at a significantly higher cost to the defence budget. Independence of operation is an alternative concept of independence and it is this which the UK has opted for at a lower price.

81. Sir Michael Quinlan told us that the UK's decision to choose independence of operation meant that "in the last resort, when the chips are down and we are scared, worried to the extreme, we can press the button and launch the missiles whether the Americans say so or not".[67] He argued that the decision to fire is an independent, sovereign decision. The United States "can neither dictate that the [UK's] force be used if HMG does not so wish, nor [can it] apply any veto—legal or physical—if HMG were to decide upon [its] use".[68]

82. Commodore Hare told us that "operationally the system is completely independent of the United States. Any decision to launch missiles is a sovereign decision taken by the UK and does not involve anybody else". He told us that the United States does not have a "technical golden key" which can prevent the UK from using the system.[69]

83. The potential disadvantage of the UK decision to forego independence of acquisition is that "if, over a very long period, we became deeply estranged from the Americans and they decide to rat on their agreements, we would be in… great difficulty".[70] Commodore Hare told us that such a risk was, in reality, "very low" and that, ultimately, "one must balance that risk against the enormous cost benefits that we have in procuring an American system to house in our submarines. That should not be underestimated".[71]

84. 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.

57 Ev 88 Back

58 Ev 51, 89 Back

59 Ev 88-89 Back

60 Ev 89 Back

61 Ev 51 Back

62 Q 42 Back

63 Ev 51 Back

64 Q 106 Back

65 Q 185 Back

66 Q 15 Back

67 Q 49 [Sir Michael Quinlan] Back

68 Ev 65 Back