Memorandum from Dr Jeremy Stocker
1. The following commentary on Cm 6994 is
forwarded in addition to evidence previously submitted to the
Defence Committee, and published in HC 986 Ev 100-103. It draws
on research undertaken for the author's forthcoming IISS Adelphi
Paper Nuclear Deterrence in the United Kingdom2. The
IISS intends to supply members of the Committee with advance copies
of the paper in advance of the Commons debate in March.
2. The current debate has often been conducted
in terms of a Trident replacement. In fact, as the White
Paper makes clear, the issue is maintenance of the deterrent,
requiring some expenditure in order to retain the existing capability.
Some components need replacement (not Trident itself),
others some refurbishment and upgrade.
3. One could therefore question why a full-blown
policy debate is needed at all. But Trident was being procured
just as the Cold War was ending. There were no major procurement
decisions then required, which might have necessitated a comprehensive
review of UK nuclear weapons policy. Though all other nuclear
systems had been eliminated by 1998, little change was made to
Trident other than the introduction of an ill-defined "sub-strategic"
capability. No comprehensive review of post-Cold War deterrence
needs has been conducted, certainly not in public, so now may
be as good a time as any.
4. The White Paper makes a compelling case
for retention of the UK's strategic nuclear deterrent, principally
on the basis of future uncertainty in a world in which nuclear
weapons continue to exist. Like previous Government statements,
it pays lip-service to eventual nuclear disarmament, but the decision
to renew the current capability makes it plain that the Government
does not expect this aspiration to become a reality within the
foreseeable future. The recognition that nuclear weapons will
remain with us is both sensible and inevitable: a nuclear-free
world is not currently on offer.
5. Para 3-4 says the focus is on preventing
nuclear attack. The White Paper does not say what role, if any,
the nuclear deterrent might have in deterring the use of other
WMD, noting that nuclear weapons are the only WMD the UK possesses.
Nuclear weapons also have a general war-prevention role as their
presence tends to induce restraint. This also is not acknowledged
in the White Paper. It does discuss their role in relation to
state-sponsored nuclear terrorism in a way that is sensible and
appropriate. Given the practical difficulties inherent in acquiring
or assembling a nuclear device, future nuclear-armed terrorism
is much more likely than not to have state support.
6. Section 3 Nuclear Deterrence in the
21st Century says more about the requirement for deterrence than
about how deterrence might actually work. The White Paper does
re-iterate the UK's policy of "studied ambiguity" as
to how and when nuclear weapons might be used. Given the "To
Whom It May Concern" nature of today's deterrence needs this
is to some extent inevitable. In a particular crisis, however,
the Government might need to be a lot more specific, and in order
to do so needs to have thought-through deterrence mechanisms in
7. The British approach to nuclear deterrence
has always been based on deterrence by "punishment":
the threat of retaliation, the cost of which would outweigh the
benefits of the original action. The other approach to deterrence
is "denial", the ability to defeat the action itself,
so demonstrating its futility in the first place. The White Paper
makes a passing reference to missile defences as potentially reinforcing
deterrence, but gives no further indication of current MoD thinking
in this area.
8. The White Paper does not deal with some
fundamental challenges to deterrence in the "second nuclear
age." Absent an overwhelming threat such as the Soviet Union,
the credibility of a nuclear response to limited aggression must
be in doubt. In particular, opponents in future crises may have
more at stake (including regime survival) than do western powers.
The latter may have "vital interests" involved but not
national or regime survival. Regional challengers may have fewer
scruples when contemplating civilian casualties, and may be willing
both to inflict and to suffer greater costs than are western governments.
The latter need to have thought-out very carefully the risks of
being self-deterred in the face of a more determined and less
scrupulous opponent. These potential difficulties with retaliatory
deterrence provide a strong imperative towards deterrence by denial
9. Cm 6994 provides a brief summary of the
UK's non-proliferation efforts, which are considerable. Curiously,
Annex A on the subject makes no mention of the most important
instrument, the Non-Proliferation Treaty (NPT), though it is in
the main body of the White Paper and in an accompanying fact sheet.
The manner of presentation suggests it is included to demonstrate
the UK's non-proliferation virtue in order to soften the blow
of nuclear weapons renewal. But deterrence and non-proliferation
are not incompatible: they seek to address the same problemproliferationby
10. The Government is right to assert that
retention of nuclear weapons is not "illegal". It is
also true that the effects on others of a British "example"
in giving up its weapons would be slight, if at all discernable.
Possession of nuclear weapons is above all a strategic matter,
in which law and morality have at most marginal relevance.
11. Annex B of the White Paper contains
an assessment of four alternative configurations for a future
deterrent capability. It is no surprise that it concludes the
present type of deterrent better meets the UKs needs than the
other options considered. Probably the most credible or attractive
alternative would be submarine-launched cruise missiles, which
is not considered as one of the four options. Cruise missiles
are examined elsewhere, however, and the White Paper correctly
concludes that ballistic missiles offer several advantages over
cruise. Interestingly, Section 4 introduces the requirement to
"deter threats anywhere in the world", which implies
that the platform and delivery system in combination must be able
to reach anywhere in the world, which only a submarine-based ballistic
missile can do.
12. The 1998 SDR reduced the number of warheads
in each submarine to 48 from a previous ceiling of 96, though
in fact no more than 65 were actually ever carried. "48"
is now replaced by "up to 48", introduced to allow greater
flexibility. Exactly 48 allows for relatively few permutations
of multi-warhead strategic and single-warhead ("sub-strategic")
13. The existing warhead can be maintained
into the 2020s. Yet to be determined is whether it can then be
extended in service or whether a new warhead will be required,
for which additional spending at AWE Aldermaston will be needed.
The White Paper does not explain why it might not be possible
to re-manufacture warheads to the present design, using the existing
stockpile of fissile material.
14. There is no mention in the White Paper
of the "sub-strategic" role for Trident. This
may be because any use of a nuclear weapon, of whatever size,
would be very "Strategic". Instead Cm 6994 makes reference
to a range of yields for the warhead, though provides no more
details. It is widely conjectured that the Trident warhead's
full fusion yield is about 100 kilotons, the same as the US W-76
warhead on which it based. By detonating only the boosted or un-boosted
fission primary, yields of about 10 or one kiloton respectively
could be obtained. If a new warhead is to be developed in the
future, the opportunity could be taken to provide a range of (probably
reduced) yields to increase operational flexibility. A further
gesture could be made in the direction of disarmament by declaring
the size of these yields.
15. The White Paper does not mention the
American Reliable Replacement Warhead (RRW) programme, though
a new warhead for Trident, if required in the 2020s, would
have much the same requirements. The US has not designed a new
nuclear warhead any more recently than has the UK, and there are
signs that future cooperation in warhead design would be welcomed
by both countries.
16. No operational justification is offered
for the 20% reduction in "operationally available" warheads.
This measure may have more to do with diplomatic and domestic
political gestures than the requirements of a "minimum"
deterrent, the minimum size of which has been repeatedly reduced
since the end of the Cold War.
17. It has been generally assumed that the
submarines are the driving factor behind current decision timescales.
However, the White Paper tells us that a decision on whether to
participate in the Trident life-extension programme is
required in 2007. This may be for programming or contractual reasons
in the United States. Whilst no firm orders for submarines will
be required for some years, it appears that a commitment to the
life-extended Trident D5A is required now. In that sense
it is the missiles driving current timescales.
18. The life-extension programme will take
Trident through until 2042, when the last of the US Navy's
existing Ohio-class submarines will be decommissioned. At that
point the RN's new boats will be between 14 and 20 years old,
with many years' service remaining. The White Paper makes clear
that the US Government has already given an undertaking that any
successor to Trident (which the US Navy needs from 2029
onwards) will be made available to the UK, and that it will be
compatible with the existing Trident launch system. This
would appear to reduce the risk otherwise inherent in putting.
submarine and missile procurements on different timescales. Trident
already meets likely future requirements, though greater accuracy
would expand targeting options. It is therefore probable that
the US Navy's replacement for Trident will look very like
Trident and may well be an updated derivative of Tridentperhaps
a D5B or D6 variant.
19. The published Exchange of Letters between
Tony Blair and George Bush contains one possibility not mentioned
in the White Paper. This could be a further Trident life
extension for UK purposes to take the missiles up to the out-of-service
dates of the new submarines (at least 2053). Such a plan would
repeat the experience with Polaris, which was kept in RN service
for several years after it had been retired by the USN. This would
put the platform and delivery system back on the same timescale,
but at the cost of getting out of step, once again, with the Americans.
The Polaris/Chevaline experience demonstrated the technical risks
and financial costs of doing so. A decision on eventual Trident
replacement will probably be required in the 2020s.
20. It is known that the submarine on deterrent
patrol usually deploys with fewer than the maximum 16 missiles,
though the Government declines to confirm how many (widely believed
to be about 12). This is surprising, in view of its greater openness
in relation to the number of warheads carried. Objectively, the
latter is the more sensitive subject.
21. Trident D5 can carry up to 12
Mk4 re-entry vehicles (RVs). The White Paper does not say what
use, if any, is made of the spare capacity. However, it is likely
that in the full multi-warhead configuration at least, a "lean/rich"
mix of inert and live RVs provides additional "bodies"
to defeat missile defenceswhich only Moscow has. It is
difficult to conceive of an operational requirement for decoys
in a single-warhead, reduced-yield configuration, so it may be
that such missiles, with a lighter payload, have an extended range,
thereby meeting the White Paper's requirement for a world-wide
22. The cost of British participation in
the life-extension programme is put at £250 million£5
million per missilewhich makes spending on Trident
itself much the smallest element of the Government's future plans.
23. he White Paper explains that the Vanguard-class
SSBNs cannot be retained in service as long as the equivalent
(but very different) US Ohio-class. The US Navy plans to replace
the latter between 2029 and 2042. The Vanguards can only be kept
for a further five years beyond their planned service lives of
25 years. From the dates quoted in the White Paper it is apparent
that the "lock started ticking"when the boats were launched
and not, as widely assumed, when they entered service. Even with
a five-year extension Vanguard herself will be decommissioned
in 2022. Cm 6994 does not actually state that the five-year life-extension
will be undertaken, but that is the implication to be drawn from
the timescales set out.
24. f the submarines are to be replaced
anyway one might question why additional money should be spent
giving the present class a modest life-extension first. The decision
to do so may be driven by the time needed to design and build
replacements, and to complete the delayed Astute-class
SSNs first. If the planned 22-month "drumbeat" of submarine
construction is adhered to, the last of the planned seven Astutes
will not be completed until around 2020.
25. The Government intends to study whether
the Continuous At-Sea Deterrent (CASD) can be maintained with
just three SSBNs. It would generate a modest cost-saving and also
provide a further disarmament gesture. However, there must be
some operational risk and a danger of undermining the whole credibility
of the deterrent by repeated pruning at the margins. The Government's
view that it is important to maintain the CASD and not opt for
a more "virtual" form of deterrent is entirely sensible.
26. Also left unanswered is the question
of how many missile tubes the new submarines will carry. Not all
the present boats' 16 tubes are used, and the planned buy of missiles
was reduced by the SDR in 1998. 12 tubes would seem to be a sensible
figure, allowing for a varied and variable number of warheads
per missile. Fewer than 12 might compromise future flexibility,
especially if a significant number of single-warhead missiles
was to be carried to address `limited' nuclear or other WMD threats.
27. The cost of the new submarines seems
very high (£11-14 billion for a four-boat force). The present
four boats cost (at 2004-05 prices) a little under £6 billion,
though in the House of Commons the Prime Minister (4 December
2006 Col 34) stated it was £14 billion (which was the cost
of the entire Trident programme). These costs may reflect
experience with the Astute programme and the fact that with a
smaller overall submarine force individual units cost more. There
is also a determination in the MoD not to underestimate costs
as any later over-runs would be at the expense of the rest of
the equipment programme.
28. The respective futures of the SSN and
SSBN forces are closely bound-up together, sharing as they do
the same Submarine Industrial Base (SIB), operating and maintenance
bases and other support, training and command infrastructures.
The SDR process identified an operational requirement for 14 SSNs,
though the number had already been reduced to 12. Treasury intervention
meant that only 10 were authorized, and this was subsequently
reduced to eight in the 2003 Defence White Paper. The current
Astute programme is for just seven boats, though 12 were originally
planned. If only three SSBNs were to be built, that could leave
the UK with just 10 nuclear-powered submarines which may not be
sufficient to sustain the SIB in the long-term. There is a view
within the MoD that the new SSBNs might be the last nuclear-powered
submarines to be built in Britain.
29. The Exchange of Letters includes the
intention to collaborate on aspects of "future submarine
platforms". The UK's first SSN HMS Dreadnought had
an American-supplied reactor and more recently some US expertise
was used to get the Astute programme back on track. Further
Anglo-American cooperation could help mitigate concerns about
the future of the SIB.
30. There are three design options for new
SSBNs: an updated Vanguard; a "stretched" Astute
or a wholly-new design. The White Paper is a little vague on this
On page 25 it refers to "changes to the design of the Vanguard-class,"
but also says that 17 years are needed to design and build new
SSBNs. An updated Vanguard would clearly not take that
period of time. The MoD wants to maximize commonality with existing
designs (mainly Astute). But the Astute-class has the same
PWR-2 reactor as the Vanguards which was designed in the
late 1970s and early 1980s. Building another class with the same
propulsion system would mean having a 1980s reactor design still
in service in the 2050s. This will probably dictate that a new
design will be developed, possibly with all-electric drive, and
why up to 17 years will be needed to bring it into service.
31. Hanging over the future of the deterrent
is the "Scottish Question". The present devolution arrangements
are viewed as unsatisfactory by large numbers of people, north
and south of the border. Most of the infrastructure supporting
the deterrent is located in England, principally at Barrow, Devonport,
Derby, Aldermaston and Northwood. But the submarine operating
base at Faslane is in Scotland. Unsurprisingly, the Scottish Question
is not discussed in the White Paper, but it was raised in the
House of Commons the same day the White Paper was published (4
December 2006, Col 35). The future constitutional integrity of
the United Kingdom has obvious implications for the nuclear deterrent.
If the latter had to be relocated, the only viable base is Devonport,
with a new RN Armament Depot probably at Falmouth. Relocation
would clearly be expensive but might be self-financing as Scottish
independence would end Westminster's funding of higher levels
of public expenditure north of the border.
32. The total cost of £15-20 billion
is a substantial sum in absolute terms, and of a scale with other
major weapons procurement programmes. Spread over the life of
the programme, it represents an average of about £1 billion
per annum, though with higher expenditure in some years than in
others. In relation to (a) overall public expenditure and (b)
the intrinsic importance of the subject, the sums entailed are
33. Of rather more concern is the opportunity
cost of the Trident programme. The Government says in the
White Paper that renewal of the deterrent will not come at the
expense of conventional forces. It has been mooted that Trident
life-extension could be funded out of a special contingency reserve,
but the White Paper only goes so far as to say that decisions
on spending for nuclear and conventional forces will be taken
in this year's Comprehensive Spending Review. This will make the
MoD nervous and the Navy in particular will worry about being
reduced to the status of a nuclear-armed coastguard.
34. The decisions the Government has made
about the future of the UKs strategic nuclear deterrent are entirely
sensible, though some difficult issues are still to be resolved.
Renewal of the deterrent must not, in any way, be at the expense
of conventional forces which are already substantially over-stretched
35. Whilst it has set out clearly the way
ahead for the deterrent, the Government has not produced a more
comprehensive strategy for dealing with the dangers and risks
posed by the proliferation of weapons of mass destruction. Nuclear
deterrence is but one tool to be used to address this problem,
one of the most acute challenges facing Britain. The country needs
an all-encompassing approach which includes diplomatic tools (including
but not only non-proliferation instruments), deterrent capabilities
(not just nuclear) and defensive capabilities (both active and
passive). But the Government's plans for Trident are an
important step in the right direction.
12 January 2007