THE UNITED KINGDOM STRATEGIC NUCLEAR JTERRENT

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CABINET MOST C O N F I D E N T I A L RECORD TO CC(82) 2nd CONCLUSIONS T h u r s d a y 21 January 1982 THE UNITED KINGDOM STRATEGIC NUCLEAR JTERRENT Previous Reference: CC(80) 29th Conclusions, Minute 1

T H E P R I M E M I N I S T E R said that, as the Cabinet would r e c a l l , the d e c i s i o n to a c q u i r e T r i d e n t to replace P o l a r i s as the United K i n g d o m s t r a t e g i c nuclear d e t e r r e n t had been announced i n J u l y 1980, f o l l o w i n g a g r e e m e n t w i t h the C a r t e r A d m i n i s t r a t i o n . The d e c i s i o n was to adopt the A m e r i c a n T r i d e n t 1(C4) m i s s i l e to be c a r r i e d i n a new B r i t i s h submarine based c l o s e l y on the A m e r i c a n submarines c u r r e n t l y c a r r y i n g Poseidon and C4 m i s s i l e s . Since then the M i n i s t r y of Defence had c a r r i e d f o r w a r d the t e c h n i c a l and f i n a n c i a l studies on the p r o j e c t w h i c h w e r e o n l y possible after the d e c i s i o n had been made p u b l i c . In October 1981 P r e s i d e n t Reagan had announced h i s d e c i s i o n to deploy the T r i d e n t 2 (D5) m i s s i l e i n 1989, and to phase out the T r i d e n t 1 m i s s i l e by 1998. The P r e s i d e n t had i n d i c a t e d that i f B r i t a i n w i s h e d to buy T r i d e n t 2 he would a g r e e . A group of M i n i s t e r s under her c h a i r m a n s h i p had been c o n s i d e r i n g t h i s question. They w e r e i n no doubt that B r i t a i n should continue to have h e r own independent s t r a t e g i c n u c l e a r d e t e r r e n t ; and that the p o s s i b i l i t y of a c q u i r i n g T r i d e n t 2 r a t h e r than T r i d e n t 1 should be s e r i o u s l y c o n s i d e r e d , p r o v i d e d that s a t i s f a c t o r y t e r m s could be negotiated w i t h the A m e r i c a n s . The choice was one o f great t e c h n i c a l c o m p l e x i t y and had considerable f i n a n c i a l i m p l i c a t i o n s . Over the whole 15 year p e r i o d of the p r o j e c t the e x t r a c a p i t a l cost of a c q u i r i n g T r i d e n t 2 would on a J u l y 1980 p r i c e and exchange r a t e basis be about £600 m i l l i o n , b r i n g i n g the t o t a l c a p i t a l cost over the p e r i o d to £6 b i l l i o n i f the d e c i s i o n were to go f o r a 4 boat f o r c e ; at September 1981 p r i c e s and exchange r a t e s the t o t a l rose to £7-| b i l l i o n . The t h r o u g h - l i f e r u n n i n g costs would be l i k e l y to be l o w e r i n the case o f T r i d e n t 2, because i t would be operating i n p a r a l l e l w i t h an A m e r i c a n p r o g r a m m e . B o t h c a p i t a l and running costs could be accommodated w i t h i n the defence budget w i t h o u t unacceptable consequences for the conventional defence effort; and i n the next four y e a r s T r i d e n t 2 would i n fact cost less than T r i d e n t 1, She therefore intended to send a message to P r e s i d e n t Reagan to suggest that a s m a l l t e a m of senior o f f i c i a l s should v i s i t Washington to discuss the t e r m s on w h i c h the A m e r i c a n s w o u l d be w i l l i n g to make a v a i l a b l e , i f r e q u i r e d , the technology, equipment and m a t e r i a l s n e c e s s a r y f o r T r i d e n t 2. When these negotiations w e r e completed the m a t t e r would be brought back to the Cabinet f o r d e c i s i o n . Meanwhile the S e c r e t a r y of State f o r Defence would be ready to a r r a n g e a f u l l b r i e f i n g , f o r any m e m b e r of the Cabinet who w i s h e d , 1 T O P SECRET

T O P SECRET on the s t r a t e g i c , t e c h n i c a l and f i n a n c i a l background to the i s s u e . It was of the u t m o s t i m p o r t a n c e that there should be no leak or public i n d i c a t i o n of the G o v e r n m e n t ' s p o s i t i o n , i n o r d e r not to p r e j u d i c e the success of the negotiations i n Washington. The r e c o r d of the p r e s e n t d i s c u s s i o n should t h e r e f o r e be r e t a i n e d by the S e c r e t a r y of the Cabinet and not c i r c u l a t e d to m e m b e r s o f the Cabinet. In the course of a b r i e f d i s c u s s i o n i t was noted that any m e m b e r of the Cabinet who w i s h e d to r e c e i v e the suggested b r i e f i n g would need to a l l o w 2-2 hours f o r the p u r p o s e . The c o m p l e x i t i e s of the p o t e n t i a l choice could not be adequately explained i n any s h o r t e r p e r i o d . I n t e r e s t e d M i n i s t e r s would contact the S e c r e t a r y of State for Defence on an i n d i v i d u a l b a s i s , o b s e r v i n g m a x i m u m d i s c r e t i o n . The S e c r e t a r y of State f o r Defence would be d i s c u s s i n g separately w i t h the S e c r e t a r y of State f o r Scotland the i m p l i c a t i o n s f o r the shore facilities required. The Cabinet T o o k note.

Cabinet Office 2 5 January 1982

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