THE Fl tD KINGDOM STRATEGIC NU AU DETERRENT FORCE - BRITAIN'S STRATEGIC NUCLEAR FORCE THE CHOICE OF A SYSTF li TO SUCCEED POLARIS On 15 July 1980 the Government published the texts of letters exchanged between the Prime Minister and President Carter providing for the United Kingdom to buy from the United States the Trident weapon system comprising Trident I ballistic missiles and supporting components for a force of British missile-launching submarines to replace the present Polaris-equipped force The new agreement is broadly similar to the 1962 Nassau Agreement Cmnd 1915 Following that Agreement and the 1963 Polaris Sales Agreement the United States sold to the United Kingdom Polaris A 3 missiles and related equip ment together with continuing spares supply and maintenance support The four nuclear-propelled submarines and the nuclear warheads for the missiles were designed and built in Britain The Polaris force as a whole is entirely owned by the United Kingdom and final decisions on its operational use rest with Her Majesty's Government alone but it is COOIIlitted to NATO and targetted in accordance with Alliance policy and strategic concepts under plans made by the Supreme Allied Coomander Europe SACEUR save where Britain's supreme national interests otherwise require The new Trident force will be acquired coomitted and operated on the same basis The Government has already shown that it attaches much importance to helping wider understanding and more informed public discussion of major defence issues The present issue is certainly a major one one of the biggest that can face any British Government in the defence field I undertook to Parliament on 28 A pril 1980 that when the Government's decision was taken l would publish as full an account as security would allow of the reasons for the choice of system This memorandum makes good that lllldertaking A few of the relevant factors cannot be published but most can be given and the Government believes they show clearly that the Trident system is the right choice for Britain Ministry of Defence July 1980 Defence Open Government Document 80 23 FRANCIS PYM - - THE POLICY BACKGROUND l 'he basic policy case for Britain ' s continuing to contn bute to NATO an independent strategic nuclear force was explained by the Secretary of State for Defence on 24 January 1980 to the House of Conrnons which after debate backed the Government I s policy by 308 votes to 52 A further account was given in paragraphs 201-20£ of the Statement on the Defence Estimates 1980 Cnmd 7826-1 The principal feature s are set out below 2 NATO's trategy is above all one of deterrence in which the possession of nuclear weapons plays a key part If we ever have to face using them the strategy will have failed in its -prime purpose That purpose is to influence the calculations 0£ a potential aggressor decisively before he embarks at all - even with non-nuclear weapons - on aggression against any NATO country The prime test of defence measures above all in the nuclear field is whether they help to make it less likely that aggressive war might be launched How they might affect the course of such a war if it once started is essentially secondary In the world of modern technology nothing can make major war anything other than appallingly destructive whether or not nuclear weapons are used The overriding objective must be to continue to prevent its outbreak The best way to ensure this is to put plainly before any possible aggressor a clear chain of i m nense risk outweighing any advantage he could hope to gain The possession of nuclear weapons is cardinal to this They cannot be dis invented the only realistic course now available is to harness their existence to the service of peace in freedom as NATO has done successfully for over thirty years 3 Britain was a wartime partner with the United States in the development of nuclear weapons We conducted our first independent test in 1952 1 and have had a full operational capability with our own de livery systems since the first V- bombers entered service in 1955 Since the late 1960s the main capabili y has been provided by the Po l aris force the effectiveness of which for the second half of its life is about to be heightened by the improvement known as Cheva line which was described to the House of f State for Defence on 24 January Corrrnons by the Secreta ri issue therefore is not whether t980 The long-termi nuciear deterrent capability but to acquire a_ strate in the 1990s after having possessed whether to give ci ions of both Conser at ve and Labour it through th e 1 forty years This 1 ssue falls to Governments for near 8 ces much less favourable for Western be settled in circum -force and Nassau decisions were xample 8 changed strategic balance security than 0 taken • there is d ore versatile all-round Soviet st and much rong ' tan t n before wielded moreover with the mili arya r s highlighted' in Afghanistan It would c nge to regard the curtai ment of our deterrent insurance as timely and appropriate now he Britain corrrnits all its nuclear capability to NATO in 4 c nfonnity with concepts of collective dete rence worked out in the joint forum of the Nuclear Plan '-1ng Grau The decisive consideration in favour of a Brit1 h c pabil ity that is ultimately independent is the contribution it makes to NATO's strategy of deterrence and thus to our own national security s The United States has massive nuclear striking power It has repeatedly made clear by its words and actions including its major force deployments in Europe its total coomitment to help defend the integrity of its European allies by whatever means are necessary without exception The Government has great confidence in the depth of resolve underlying the United States conmitment But deterrence is a matter of perception and perception by a potential adversary The central consideration is what that adversary may believe not what we or our Allies believe our deterrence has to influence possible calculations made by leaders whose attitudes and values may differ sharply from those of the West The decision to use United States nuclear weapons in defence of Eu rope with all the risk to the United States homeland this would entail would be enormously grave A e leadership - perhaps much changed in character from Y s perhaps also operating amid the pressures of turbulent internal or external circumstances - might believe t it could impose its will on Europe by military force Un hout becoming involved in strategic nuclear war with the ted Sta tes Modernised US nuclear forces in Europe help r aina t any such misconception but an independent 1 el ent ully under European control provides a key nsurance A nuclear decision would of course I be no less agonising for the United Kingdom than for the United States• But it would be the decision of a separate and independent power and a power whose survival in freedom would be directly and imnediately threatened by aggression in Europe The nuclear strengths of Britain or France may seem modest by comparison with the superpower armouries but the damage they could inflict is in absolute terms immense A single Polaris submarine carries more explosive power than all the munitions used in World War II An adversary assessing the consequences of possible aggre sion in Europe would have to regard a Western defence containing these powerful independent elements as a harder one to predict and a more dangerous one to assail than one in which nuclear retaliatory power rested in United States hands a lone 6 Our contribution to the Alliance in this field is unique France like Britain has powerful nuclear forces under independent national control but her distinctive policy - well understood long established and firmly held debars her from undertaking the clear corrmitment to collective Alliance deterrent concepts planning and strategy which we have made No other European member of NATO is even remotely a potential candidate to contribute independent nuclear forces The Government regards this distinctive British contribution to NATO as of great importance Our Allies recognise its significance as they made clear for ex ample in the 1974 Ottawa Declaration of the North Atlantic Council 7 British nuclear forces include both strategic and lowerlevel components If we had only the latter they could not serve the key second-centre deterrent purpose since the threat of their use would not be credible An aggressor faced with an armoury comprising only non - strategic nuclear weapons would know that he could if necessary use strategic nuclear weapons to overbear it without risking strategic retaliation upon himself and since he would know that his opponent too must realise this he could be confident that the non-strategic weapons were most unlikely to be used The harsh logic of deterrence requires that the nuclear decision-maker should have evident power to take his resistance all the way to the strategic level if the aggressor will not desist If Britain's nuclear contribution to NATO is to fulfil its distinctive role in deterrence it must include an effective strategic element 4 3 ba the Cove-i cloea not ballfla - - - - afa -1 d be adequately • t by a --1 ility oaly- a low likelihood of striking home to key OI which poaed the prospect of only a very -11 o9'8trlku or which Soviet leaders could expect to -off niCCe• afully from large areas of key importance to They llight even be tempted to Judge that if an equipped himself with a force which had only a tilbdut of inflicting intolerable damage there might he only a IIDdut chance that he would have the resolve to ·uaa lt at all 12 Succeesive United Kingdom Goverrrnents have always daclined to make public their nuclear targetting policy and plana or to define precisely what minimum level of destructive capability they judged necessary for deterrence The Governnent however thinks it right now to make clear that their concept of deterrence is concerned essentially with posing a potential threat to key aspects of Soviet state power There might with changing conditions be more than one way of doing this and some flexibility in contingency planning is appropriate It would not be helpful to deterrence to define particular options further The Gove't11118nt however regards the considerations noted in paragraphs 10 and 11 above as important factor • in lecidhlg the scale of capability we need d First the potential war the nuclear age are 15 The answer is consequences of any deterrent insurance against even so i amense that some t outbreak is warranted and remote possibilities f h strategic nucle r forces is exceptional rea ine d least costly form of insurance the most effective ttack Second it is in part against massive surp s n uranc is maintained that we can precisely because rce plans on the ass ption that a frame mo t of our -the-blue is very unlikely it might nuclear bolt- romhan ed NATO dispositions seemed to offer 1 not remain so e l c nce of disarming us by a sudden an adversary 8 b lieves therefore that we must st ike 'he Go r t e standards of immuni y to main da-p e emptive attack which the Polaris force Sp achieved so successfully since the 1960s t w st in l6 No-one can define now exactly when the Polaris f rce will have to be phased out There are complex o erational and technical factors some of them hard to predict and the likely prospect in several respects is of gradually declining effectiveness and mounting cost and risk rather than abrupt cut-off points or failures though the possibility of these cannot always be ruled out 17 though the Chevaline prograume will keep our Polaris missiles able to penetrate anti-ballistic-missile ABM defences into the 1990s continuing Soviet effort in research and development allowed by the 1972 ABM Treaty might in time reduce our assurance of this and growing Soviet competence in anti-submarine warfare ASW backed by a huge investment of resources must tend in time to erode our current advantage and eventually make our submarines built to designs now twenty years old and not capable of being further modernised less immune from detection and attack It is clear from our own and US experience that hull life can last beyond the twenty years originally envisaged but it is not extensible indefinitely and in any event the on-board equipment - propulsion machinery missile support systems and the like - is ageing and must at best pose a heavier maintenance load with a growing risk that refit periods may be so prolonged or unexpected defects at othe r times so serious that continuous patro l would be l os t I n addition the age of the systems and the pro s pect that t he phasing- out of Polaris from United State s ser vic e i n 1981 will leave the costs of maintaining support c apabi l i t y for it to be borne entirely by the United Kingdom will make t he force increasingly expensive to keep going 18 Amid t h ese uncertainties and risks the setting of a particula r date for retiring the Polaris force must be a matt er for judgement This judgement must take into account the fact t hat the British force unlike its United States count er part i s not part of a powerful triad of complementary strategic forces land - based ballistic missiles in silos long-range bombers soon to carry cruise missiles and s ubmarin e-launched ballistic missiles and that it is more· over of modest size with no insurance margin We must consider h ow long the force would last not only if matters went we l l but a l so if they did not Against all this background I the Government has concluded that responsible pla nning must look to progressive replacement of the present force beginning in the early 1990s 19 In the 1960s special efforts made it possible to have the f ir st Po l aris boat operational less than six years after the Nassau Agreement was signed Systems are now more complex a nd sever a l critical lead times are now much l onger If we are to br ing a new missile submarine force into ser vi ce on time design wor k f or the boats themse l ves a nd other key force componen t s mus t begin s oon This has se t t he t imetable for studying all t he s ystem options 20 Paragraphs 16-18 have discus sed when a new force should enter service But we have to consider also how long it should last Re-equipment is very costly arrl we cannot afford to undertake it as often as the super - powers Ideally we should like any new force to remain effective as the Polaris force will have done for at least twentyfive years - well into the second decade of the next century To give high probability of this we need to choose a system which represents a b g enough advance in capab lity to rovide some margin to meet the greater operational demands hich continuing efforts on the Soviet side must be expected to impose Re-equipment providing only a small advance in capability could before long prove a false economy and our •L attractions They cost much less each 38 CMs have they are even more accurate they than Trident m1 5 s1 1 r and easier to store The fact that are a good deal ma ther than minutes to reach targets they would take our r ot important since Western in the Soviet Uniondis ot envisage trying to catch Soviet deterrent concepts o n missiles in their silos• 9 There are however major factors on t e ot er side United states judges that present Soviet air defences with advan ing technology th defence problem is not insuperable given time and ef ort and Soviet defences against CMs unlike ABM defe1 ces are not limited by Treaty It is imp ssib e to put precise figures on what proportion of CMs Soviet a1 r defence in the two decades from the early 1990s - r ughly the t eframe we want for our new strategic system - might succeed in shooting down· but we arust reckon with the possibility that it could prog essively become very substantial especially since we probably could not afford to re-equip with new and better CMs as often as the United States may wel 1 do to keep pace with defences in this new and rapidly changing field We have to take into account also that whereas the United States ALCM force can plan to saturate the defences of key strategic targets we could not operate on the same scale In addition the apparent advantage of CMs over BMs in cost per missile is misleading Trident can carry up to eight separately-targettable warheads current CMs carry only one and SALT II would prohibit CMs carrying more ih have little chance against CMs but 40 There are also considerations affecting the submarine We like the United States have always judged it important that a strategic missile submarine should be able to fire its weapons within a short space of time to avoid the risk that enemy action - by ASW forces or by counter-battery fire from land-based ballistic missiles after the larmch of our own missiles had perhaps revealed the submarine's position • might be brought to bear before all the missiles had been fired Our Polaris boats accordingly can fire their full complement within a very few minutes But this is much more difficult with CMs 1 ith torpedo tubes - the only submarine-launch mode ao far developed - repeated re-load would be necessary to latmch a number of CMs anywhere near equivalent in striking power to a boatload of l'Tident BIia • The process would take hours during which the 15 s ubmarine would be at increasingly severe risk and it might well not survive to complete the task Aiternative l aunch modes such as vertical launch on the SLBM pattern would require extensive new system development and ' submarine design The United States has made some preliminary study of using such modes on a limited scale in hunter- killer submarines but there is no United States evelopment programne Without such a prograrmne which even if undertaken might not match British strategic needs the burden of development would fall entirely on us if we wanted such a solution 41 There is a further operational point Current CMs have much less range than BMs j moreover at least with systems now in prospect there is a limit on how far off-shore a l and- attack CM can be launched since beyond a certain distance cumulative inertial- navigation errors may mean too high a risk that the missile will fail co make its landfall accurate l y enough to initiate the over-land navigation phase successfully The effective range of a CM launched from the North Atlantic would be significantly less than that of Polaris The sea-room available to the submarines and t heir scope for evading improved Soviet ASW forces w uld be restricted accordingly Further technical development might well ease this restriction but since it is not important to the major United States applications of CMs we cannot tell when or at what cost 42 The factors in paragraph 40 relate essentially to a CM-launching submarine devoted entirely to the strategic role We a l s o considered the possibility of equipping each of our hunt er - k iller submarines with a small number of CMs for l aunch through t he torpedo tubes But t here a r e two di ff i culties about this Fi rstly there is the pr obl em of c onfl i c ting ta sks of the general kind a l ready noted i n paragraphs 28 and 30 Our non-strategic subm e rin e forc e is already fully c otmtitted to its existing t asks and the patterns of deployment and operat i on f or the last-res ort strategic role are very different from those for seeking out and attacking other submarines and surface ships Secondly it would not be possible to build up enough strike capability 11 11 for strategic deterrence in penny-packet numbers of CMs on non-strategic submarines 16 ls All this means that CMs are not in fact a cheaper option 43 BMs For a given weight of striking power and a given ev l of· probability of delivering t successfully CM-based forces are in fact much more expen ive For example eleven boats each capable of carrying eighty CMs would give less assured deterrent capability than a force of five boats each with sixteen Trident BMs and it would cost at least a third as much again to acquire and about twice as much to run One of the major reasons for this important to bear in mind in all evaluation of delivery system options is that for almost any submarine force the boats are a m ich more costly element than the missiles Ballistic Missiles 44 It would not be impossible for British industry to develop and build ballistic missiles for strategic use We have however had no major capability in this field since the 1960s and to re-acquire it now would be very expensive take a long time and involve much uncertainty This cannot be an attractive option 45 The present Polaris missiln could be kept and fitted into new sullaarinea They would need new motors produced fraa restarted prod tion lines1 this may be necessary any•Y to mtch preamt f - life not 10 certainly or on IO large a scale n would be needed if the missiles were qi pt 1 eyoQd the -3 y 1990• lfuch of the missile support equipment would need to be replaced at the outset and this would be costly and difficult particularly as much of it would have been long out of production Removing equipment from the present boats and fitting it into the new ones might not be cheap or easy and would entail major problems in maintaining continuous operational capability during the transition the alternative of new manufacture for all the equipment would be very c ostly especially as moa t of it is already long out of production The missiles and related equipment afloat and ashore would be coat Y to maintain both because of age and because spares eplacements would increasillgly have to be specially eded technological standards long since superry It would be necessary to buy extra • 11ea - 1DII out of production - and extra Chevaline i e l ements to support the force for longer Moreover unless we were to make the very bold assumption that Polaris missi l es would remain satisfactory until beyond 2010 we should have to build submarines capable at some point in t h eir life of accoltlilodating a different missile of a type which since Trident production will not continue indefinitely we could not easily predict now 46 For all these reasons a force based on t he existing missiles in new submarines would not be cheap and perhaps not highly reliable Nevertheless it would be cheaper initially than an entirely new force in capital cost - in very broad terms possibly by around forty per cent though subsequent running costs would tend to be higher Such a saving would in itself be highly valuable The difficulty is that the resulting force would be of uncertain value and short life For operational reasons a force based on Polaris - even with the Chevaline improvement designed essentially for the forecast envi'rorvnent of the 1980s and early 1990s - would be able to maintain a high deterrent assurance in the later 1990s l et alone beyond that only if the advances in Soviet ability to counter it proved unexpectedly modest If such a hope were disappointed we should be faced with a choice between keeping a force of much reduced deterrent credibility and effectiveness and changing our plans at short notice Such a change would certainly have to be made at high cost and probably in haste wasteful ly and with difficulty It would be seriously irresponsible t o undertake on such a bas is what woul d still be by any standards a major investment 47 We con sidered a ls o various possibil ities for acqui ring new versions of the basic Pola r is mi s si le improved mainly by the us e of mor e modern and power ful r oc ket f ue l s to give more r ange and payload t hough short of Tr i dent standards a s an i nsurance against improved Sov iet c apabilities Any of thes e possibil i ties wou ld entail a substantial R D programme covering the mis siles themselves the altered interface with Chevaline and related equipment The procurement costs - which cannot be assessed as firmly as those for the already operational Trident system and carry greater risk of escalating - would have fallen entirely on Britain as would all the costs of setting up and sustaining support arrangements for a system that had never been in 18 ls United States service The amount would depend on how big an improvement over the present Polaris capabilit was sought but missile system costs could well be twice those of Trident for a smaller and less assured capability Moreover concerns like those in paragraph ii would arise about effective operational life though perhaps less quickly 48 Another possibility considered at an early stage was a European solution Collaboration in the European context could have been of considerable political significance But it was soon apparent that this option had a number of disadvantages in particular related to cost There is no likelihood that the United Kingdom could have acquired by this route an effective deterrent force at a cost either in initial investment or in subsequent support which could compare with that for the proven Trident system especially when account is taken of the economic advantages of our long-established arrangements for collaboration with the United States it1 nuclear forces The Government therefore sees no adequate basis on which such an option could now have been pursued 49 We considered also the adoption of the Poseidon system hich the US would have been willing to make available when it begins to phase out of US service by about 1990 Poseidon en ered s rv ce in 1971 is of the same size as the present Trident missile and is a MIRVed system capable of carrying u to fourtee warheads of substantially smaller size and yield than Trident or our own Polaris Range varies with payload but with a reduced number of warheads it is about 300 nautical miles more than that of Polaris A 3 50 Poseid n would be an effective system but particularly because of its shorter range it would offer less long- term ins ance than Trident against improved Soviet capabilities The initial purchase price would be lower but several ot er facto s offset this The age of the missiles and r ated equ1 pment would mean higher maintenance cos ts and o tui rtainly a major re - motoring prograrrm e before' long fe s O have to bear all the continuing support costs • 8 st a o em no longer in United States service We should d e to undertake a very extensive British warhead 1 t v d e e t ting prograume and perhaps further work unlikely that t s e system to our warheads In all it is be less good e cost would be lower and the system would a 51 Trident I is a three - stage ballistic rocket designed to car ry up to eight independently- targettable warheads The maximum range is from about 4 000 to 6 000 nm depending on t h e number of warheads The first missiles went to sea on operational service with the United States Navy in 1979 They are initially replacing Poseidon missiles in some existing submarines and they will later be fitted in the new OHIO- class submarines MIRV capability and long range give excellent margins of long-term insurance against further advances in Soviet ABM aDd ASW capability i and improved guidance techniques give better accuracy than ear l ier systems have offered The Trident system is likely to remain in United States service for many years to come during which all the economies of commonality will be ava i l able to us 52 We considered whether there would be any advantages i n a non- MIRV Trident MIRV capability is however i ntegra l to the system design and deliberately to remove it and substitute MRV capability would entail a major r e - design and re - testing progranme leading to a missile degraded in performance and unique to Britain Missile system costs would probably be at least double those of Trident for a greatly reduced capability A de - MIRVed Trident would have the additional disadvantage - common a l so to the Polaris - based options discussed in parag- caphs 45 - 47 - that it would offer much less insurance than the f u ll system against any possibity that in the long term ABM defences might not remain unde-r the present Treaty c onstr aint s 53 A concept for a lar ger SI BM known as Trident II is being s tudied in the United States and the OHIO- c l ass submarines will be big enough to take such a miss il e It would give still grea ter range and pay l oad naturally at higher cost The US Government however is no t expec ted to decide for another two or t hree years whe the r to proceed with Trident II Our own c hoice now could not be made dependent on uncer t ain possibiliti es like this MRV multiple re-entry vehicles not independently target table MIRV multiple independent l y- targettable re- entry vehicles 19 20 ls Force Size 54 There are two main variables to force size th n ber of missiles per submarine and the number o submarines They interact in some degree The O timum number of missiles per submarine involves 5 ompromi e between conflicting factors For a given total complement of missiles the fewer the boats the low r the cost but also the greater the risk of to many eggs 1 n one basket _ this last being a particularly important consideration for a relatively small force like our We considered eight twelve sixteen and twenty four m1 ss1 les per boat Of these options twenty-four as 1n the very large United States OH IO submarines is more than we need given that we have to have at least four boats nyway as paragraph 56 explains At the other extreme e1ght missiles would lead to a much larger number of boats for a given total capability and th is drives up costs and manpower demands The choice between twelve and sixteen is less clear-cut but on balance we believe it best to plan for sixteen which is the number used in our present force the French SLBM force and the United St ates Polaris and Poseidon forces and also most of the Soviet SLBM force 57 No immediate decision is needed on the choice between f our a nd five since major expenditure related only to a fifth boat woul d not arise for two or three years from now Th e Govenunent intends therefore to keep the option open and t o t ake a final decision in 1982 or 1983 in the light of the l a t es t information and judgements on relevant operational in t ernational and resource factors including the defence budget situation ls 56 Deciding the number of boats is more difficult Four is the minimum needed to sustain without fail at least one always on patrol System improvements may improve the ratio of operational to non-operational time but not to the point at which a force of three submarines could be sure of sustaining continuous patrol for more than a few years A force of five can maintain two on continuous patrol yet because force overheads do not rise proportionately with numbers the extra cost would not exceed fifteen per cent A fifth boat would also offer a margin of insurance against possible risks such as marked relative improvement in Soviet ASW or losing a boat by accident or major unforeseen defect But the skill and dedication of our personnel have enabled us to manage successfully with four boats for over a decade and the extra capital cost of a fifth in the Trident era t ough modest in proportionate terms is still very large 1 n absolute terms - perhaps in the order of six hundred million pounds 21 22 IV - ARMS CONTROL 58 Throughout its consideration of Polaris replacement th Government has kept in mind the relationsh p between its prospective decision and arms control considerations Strong support for practical balanced and verifiable arms control measures remains a key element in our a proach to ensuring peace and security The Government like all its allies in NATO much prefers arms control to arms expenditure whenever the circumstances an l the will on both sides of a potential agreement make this an effective alternative 59 The Government believes that the implementation of the bilateral US Soviet SALT II agreements signed last year in Vienna is in the interest of international security and keenly hopes that conditions in which ratification can go ahead will soon be restored The decision to modernise our own strategic force in the 1990s is entirely compatible with this view The continued Anglo-American cooperation provided for in the exchange of letters on Trident is fully consistent with the terms of the SALT II Treaty and indeed this long-established cooperation was clearly in the mind of the United States as Congressional testimony has indicated when it rejected Soviet demands for no-transfer provisions The scale of our new capability will in no way disturb existing and prospective East West relativities For example even if we eventually choose to go to the higher figure of five boats when the force was fully operational in the mid-1990s it would represent in relation to Soviet strategic forces at that time assuming these to be limited to SALT II levels about the same proportion of delivery systems as - and a rather lower proportion of warheads than • the Polaris force did in relation to Soviet forces when it was completed in 1970 disarmament in accordance with Article VI of the Treaty For example the Government continues to support the conclusion of a Comprehensive Test Ban Treaty and we are participating fully in the Geneva negotiations with the United States and the Soviet Union Nothing in our requirements for the new force will lead us to modify our support for a successful outcome to these negotiations as soon as practicable 61 But nothing in the Non-Proliferation Treaty requires the existing nuclear powers unilaterally to abandon or let decay their basic capabilities which are inescapably a key part of the established structure of global and particularly East West security whose collapse would bring grave dangers for all nations Moreover the Government sees no -realistic ground for supposing that unilateral gestures of renunciation by Britain - gestures which thexe is not the slightest l ikelihood that any other nuclear power would emulate would make any marked or lasting difference to the prospects of accession to the Treaty by those comparatively few nations which might be capable within a reasonable time of acquiring some nuclear weapons capability but whose assessment of t heir own national interest has so far led then to decide against accession 62 Finally Britain's strategic S1 BM force lies out side the category of those United States and Soviet long- range land - based theatre nuclear forces about whose limitation the United States last December invited the Soviet Union to negotiate 60 The Government strongly supports the regime established by the Non-Proliferation Treaty of 1968 and hopes to see it extended by the accession of more countries and the development of a broader international consensus on the terms of nuclear trade The Review Conference of the T eaty will be held in August 1980 and the United Kingdom will play a full part The Govermient remaiillcoomitted to pursuing negotiations on effective measures of nuclear 24 23 ls ro osed Trident force cannot be 63 The costs of thde P_lP t this stage - further discussions estimated in close eta1 a d are needed with the United States auth rit1 es' an in several respects such as submarine design and numbers the costs will depend upon decisions which ve yetr r b f taken In broad terms however we assess the 11 kelr O capital cost for a four-boat force at today s prices at around four-and-a-half to five billion pounds spread over some fifteen year Rather over half of this woul be likely to fall in the 1980s The total would cover submarines missiles warheads and support equipment and facilities including new construction required at the Coulport armament depot the Faslane operating base and elsewhere 64 Of the total initial cost over seventy percent w ll be spent with British establishments and industry the biggest elements being in shipbuilding construction and warh ad procurement The Government will seek every opportunity that is economically and operationally sensible for British industrial participation so as to bring the proportion to a maximum although to increase it very markedly would be likely to entail substantial extra capital or running cost 65 There has rightly been widespread public interest in the effect which the replacement of the Polaris force will have upon other aspects of the defence programme Money spent on this is money not spent on other things If it can be assumed that future total allocations to defence would be no lower without Polaris replacement than with it forgoing Polaris replacement would obviously make it possible to fund additional or earlier force improvements somewhere else 66 It is however important to keep in view the scale and significance of this from several standpoints The capital cost of the Trident force will be spread over about fifteen years The Government's expenditure plans announced in the most recent White Paper on Public Expenditure provide for defence spending to rise by 3% a year in real terms over each of the next three years giving by 1983 84 a budget some 13% higher in real terms than in 1979 80 No- one can be sure exactly what the size of the budget will be in the ten years thereafter but the capital cost of the Trident programne is unlikely to absorb on average more than 3'7 of the total budget between 1980 and 1995 The equipment element of the programme is unlikely to absorb more than 5% of the equipment component of the defence budget over this period The total cost might absorb some 1 '¼ of the total during the build--up in the first half of the 1980s some 5% or 8% of the equipment component in the main spending period from 1985 to 1990 and then 1-2% between 1990 and 1995 We spent much higher proportions in the 1950s on the build-up of the V•bomber force Even after spending on the Trident force the Government is still planning to spend more on conventional forces than it does now The accoamodation of large re-equipment programmes is a normal part of defence planning and budgetting Tornado procurement costs more than the estimated cost of the Trident force and is currently absorbing some 7% of the defence budget without distorting the rest of the defence programme Once capital investment is past the Trident force should be notably inexpensive - probably well below 2% of the defence budget from the mid- 1990s In terms of manpower which may increasingly become a key constraint upon our defence effort the Trident force should be broadly as economical as Polaris which r1 quires only 2500 servicemen under 1% of Service manpower 67 There are accordingly no easy comparisons to be made with other defence capabilities There would be little point for example in diverting the full capital sum to buying more ships tanks or aircraft which in the long term we could not afford to run and could not hope to man The rising real cost of defence equipment is a general cause for concern but this problem is not specific to the Polaris successor For all these reasons impressions that we could sustain much larger conventional foTces without Polaris replacement than with it are well wide of the mark Cmnd 7841 26 25 ls 68 As the Prime Minister ' s letter to President Carter makes clear the Government is convinced and determined that the provision of the new Trident force should not prevent or emasculate continued improvement in other areas of our contribution to NATO It believes moreover that the modernisation of the independent British element in NATO ' s strategic nuclear forces is a central element of that contribution not a luxury or a diversion No alternative use of British resources would provide a comparable strengthening of collaborative Alliance deterrence to aggression 27 • ••