shifting to minimum deterrence

8/14/2019 Shifting to Minimum Deterrence

1/17

NAVAL WAR COLLEGENewport, R.I.

Going Low Order:Shifting the United States to Minimum Deterrence

ByScott Minium

Captain, United States Navy

A paper submitted to the Faculty of the Naval War College in partial satisfactionof the requirements of the Department of National Security Decision Making (Security, Strategyand Forces subcourse)

The contents of this paper reflect my own personal views and are not necessarily endorsed by the Naval War College or the Department of the Navy.

Signature:___________________

25 JAN 2010


2/17

Going Low Order:Shifting the United States to Minimum Deterrence

Current U.S. nuclear deterrent strategy and force structure remain rooted in Cold War

dogma. While the number of operationally deployed strategic weapons has declined ten-fold

since its peak in the 1960s, the number of systems designed solely to deliver these weapons

has declined at a much slower rate. The result is a substantial number of U.S. nuclear forces

that consume resources even though they are not essential to national security. A

reassessment of the security environment demonstrates that a revised strategy of minimum

deterrence 1 can be implemented that not only provides security, but also cuts the number of

deployed nuclear weapons and significantly reduces the resources required to field those

weapons. 2

Past: The Cold War, the U.S. and the U.S.S.R.

Deterrence is the prevention of a choice of action through the promise of a penalty for

that action. Nuclear deterrents are maintained by state actors for primarily two reasons: to

dissuade others from using nuclear weapons at all, and to ensure the continued existence of

the state. In the first case, one seeks to enforce the international norm of no nuclear weapons

use by threatening retaliation with the same. In the second, a state prevents its dissolution by

promising severe consequences for any state making the attempt. 3 All deterrent strategies can

be characterized as one of two types: denial or punishment. Denial seeks to prevent an

adversary from achieving a desired end state, for example victory conditions in a war.

Historically, this has used a large number of weapons to hold military and industrial centers

at risk. This has also been referred to as a strategy designed to counter war-fighting.

Deterrence by punishment, on the other hand, threatens an aggressor with unacceptable

1


3/17

losses in response to an attack. While deterrence by punishment has a broader target set,

including not only military but some industrial and population centers, it is generally

reasoned that this kind of deterrent is effective with comparatively fewer numbers of

weapons. Theoretically, the deterrent strategy should be selected by each side on the basis of

what is assessed to deter the other; however, the U.S. and its adversaries did not make such

unilateral determinations.

People, especially Americans, like to think things happen by design. Our deterrent,

however, was more the result of a co-evolutionary process. At the start of the Cold War, the

U.S. and the U.S.S.R. embarked on a deterrent journey that even now locks them together. Inits infancy, deterrent theory sought to do no more than prevent an all out warincluding a

conventional one in Europe. As stated above, deterrent strategy should be selected based on

what an adversary prizes. It was probably simple for the U.S.S.R. to conclude that the U.S.

greatly valued its population and way of life. The Soviets, therefore, adopted a strategy of

deterrence by punishment. This model required a relatively small number of weapons, and

since it included soft targets like population and industrial centers, the weapons did need

not be accurate. This targeting doctrine has also been called countervalue.

The U.S., on the other hand, concluded that the Soviets did not care about anything so

much as their war machine. Furthermore, the U.S. assessed that the Soviets considered a

nuclear war to be winnable if enough forces were retained after an exchange. The Soviets

were thus assessed as pursuing a war-fighting strategy. However, because the technology at

the time precluded accurate strikes against hard targets like missile silos, the U.S. initially

adopted deterrence by punishment. As soon as sufficiently accurate weapons became

available, the U.S. shifted to deterrence by denial. The U.S. thus sought to deny the Soviets

2


4/17

any chance of attaining victory conditions by targeting every missile silo, military-industrial

complex and military base. This not only required a large number of weapons, but also a

variety of platforms to improve the survivability and credibility of the deterrent force. 4 The

numbers required for such counterforce doctrine gave it another name: maximum deterrent.

The stage thus set, the co-evolution of deterrence proceeded apace. The U.S. first

adopted countervalue due to technological limitations, but once technology allowed,

counterforce was adopted to better deter a war-fighting adversary. The Soviets, who at the

time possessed only a countervalue capable force, looked at U.S. efforts to build a survivable

and broad based deterrent and concluded the U.S. was a war-fighting adversary. With bothsides observing the other doing the same thing, each countered it the same way, and the stage

was set for an arms race of truly epic proportions. At their peak in the late 1960s, U.S. and

Soviet arsenals reached a total of over 50,000 strategic weapons. 5 Arguments from the early

1960s about how much is enough were completely dismissed, and the only perceived way

to deter was with near equality of numbers. Uncertainty in intelligence estimates constantly

put the adversary ahead, which meant more was always neededand quickly. Arm in arm

the two super powers marched toward steadily larger numbers of weapons and systems until

arms reductions began in the 1970s.

Along the way two significant technological steps forced changes in deterrence. The

first big change resulted from the increased accuracy of intercontinental ballistic missiles

(ICBMs). ICBMs were not very vulnerable to missile attack when first fielded, but once

accuracy improved it became possible to eliminate this part of an adversary's arsenal with

long range missiles. With about 30 minutes from launch to impact, ICBMs now had to be

launched quickly or risk being lost altogether; thus making them first strike weapons. The

3


5/17

resulting use them or lose them dilemma moved both sides to develop early warning

systems to enable launching of ICBMs as soon as inbound weapons were detected. This

destabilizing stance, called launch on warning, is retained to this day by the U.S. and Russia,

and it is the main reason ICBM numbers were the first targets of arms reduction.

The next developments in deterrent logic came as a result of submarine launched

ballistic missiles (SLBMs). SLBMs, for the first time, ensured a portion of the deterrent was

fully survivable. It was stabilizing in that it did not require launch on warning and could

promise a retaliatory second strike. Once SLBM accuracy allowed targeting of ICBMs, the

SLBM became a survivable first and second strike weapon. This development greatlyincreased the value of the SLBM, leading ultimately to the U.S. having the majority of its

deterrent in submarines. 6

Past and Present: the Rest of the World

It is interesting to note that among the major nuclear powers only the U.S.S.R. and the

U.S. adopted maximum deterrents consisting of thousands of weapons. While it is possible

the other major nuclear powers did not do so because of the cost, the fact remains they are

still satisfied with their deterrent. The UK and France maintain small deterrent forces in

ballistic missile submarines (SSBNs), and both countries maintain some SSBNs on patrol

and survivable at all times. France initially possessed air and land based weapons, nearly all

of which were removed from service when they launched SSBNs. The UK, on the other

hand, has dismantled all of its deterrent with the exception of SSBNs. It has been argued that

the primary reason for the small deterrent forces of the UK and France are due to extended

deterrence, the so-called American nuclear umbrella. That is, the UK and France count on

the U.S. deterrent to provide enough of a threat to be credible. This criticism may be valid if

4


6/17

they desire to deter through counterforce; however, each force constitutes a powerful

punishment deterrent by itself. 7

China was the last of the major nuclear powers to develop weapons, detonating their

first in 1964. China has a need to deter both Russia and the U.S., but despite the large

numbers of weapons held by its potential adversaries, it has always maintained a very modest

size force. It is also interesting to note China did not even possess weapons that could range

the U.S. until the 1980s, 8 and the Chinese deterrent today still consists almost entirely of

land-based missiles. The Chinese have their own way of looking at deterrence, but whatever

label is put on it, clearly it is intended to deter by punishment. Importantly, China, with adeterrent force much smaller than either France or the UK, successfully deters both the U.S.

and Russia. 9 What these other countries demonstrate is that deterrence can be obtained with

substantially smaller numbers of weapons.

Present: the U.S.

Most people would likely be surprised to find out just how small U.S. and Russian

nuclear arsenals are today. The effect of numerous treaties and agreements has brought the

number down to between 2000 and 2500 deployed warheads. President Obama has stated a

goal of no nuclear weapons, but realistically this remains a distant objective. The current

stated target is between 1700 and 2200 warheads. However, it is worth noting that the

reduction in warheads has not been matched by an equal reduction in delivery vehicles.

The first Nuclear Posture Review took place in 1993 shortly after the end of the Cold

War. Since then these reviews have been conducted about every four years. While the

number of warheads has declined by half since 1991 10, the NPR process has consistently

validated the number of delivery vehicles and platforms as is demonstrated by their

5


7/17

continued existence. 11 The number of delivery systems has not changed substantially since

1992, although, to be fair, the U.S. has dismantled the Peacekeeper missile system and

converted four SSBNs to conventional armaments. However, the U.S. still maintains 500

Minuteman III ICBMs (each with one warhead), fourteen SSBNs with twenty-four SLBMs

each (336 missiles and nominal 2688 warheads), and about 230 nuclear capable bombers. 12

The risk of continuing to maintain all of these systems is the inherent desire to replace

them when they reach the end of their lives. For example, the U.S. Navy is currently

researching a plan to replace twelve of fourteen SSBNs starting in 2029. Funds for these

future ships will begin to be allocated around 2016. Additionally, the certain trend towardsmaller numbers of warheads makes each of the new platforms proportionately less cost-

effective than the unit it is replacing. This is of particular interest for SLBMs, where cost of

the delivery system is driven overwhelmingly by the cost of the submarine itself, and the

system is only cost-effective if it carries a large number of warheads. 13 The cost-effectiveness

of any replacement systems must be estimated using reasonable numbers of future weapons

in order to ensure alternatives are fairly reevaluated. More on these possible alternatives in a

moment.

Future: The Tyranny of Small Numbers

The process of arms reductions started in the 1970s has been continued by every

administration since, and this is likely to continue in the future. The reduced numbers of the

future both allow for and require different delivery systems as well as mandating a change in

deterrent strategy, but for different reasons.

First, although the number of nuclear weapons is likely to decline, there is no reason

to believe that conventional forces will follow this trend. Since counterforce targets

6


8/17

conventional and nuclear forces, there is a point at which counterforce becomes numerically

impossible. A minimum deterrent, one based on punishment rather than denial, is an

effective alternative. Such a deterrent is countervalue, but it need not follow the 1950s model

and target cities. Instead, it holds at risk both nuclear forces and the infrastructure necessary

for modern civilization to function. 14

Second, as the number of warheads decreases, the per warhead cost to replace

delivery systems grows proportionally. At this time each ICBM in the U.S. inventory carries

but one warhead, making a replacement much more costly on a per warhead basis than if

they each carried the two or three warheads of the past. SSBNs, while very expensive to build, are cost-effective because they each carry a large number of warheadsnominally

eight in each of 24 missiles. However, START-II, had it entered into force, would have

reduced the number of warheads per SLBM to four 15, thus halving the effectiveness and

doubling the cost per warhead of any replacement. As will be discussed later, this trend

toward fewer numbers and fewer warheads per vehicle is likely to continue regardless of

arms negotiations. Although this will most adversely impact SSBN cost-effectiveness due to

the cost of the submarine, submarine enthusiasts point out the one unique advantage provided

by SSBNs: their near certain survivability.

But while SSBNs may be the only survivable deterrent force in the U.S., both Russia

and China have fielded an alternative: the land-based mobile ICBM. The U.S. explored these

weapons for over thirty years before canceling the program in the early 1990s because it was

simply not cost-effective compared to SSBNs. With each land based missile, and thus

essentially each warhead, needing its own crew and support system, the cost per warhead was

easily beaten by SSBNs in spite of the cost of the submarine. However, declining numbers

7


9/17

require this calculation to be revisited. And while there are many variables in this equation,

with current numbers the land-based mobile missile becomes the cost-effective choice to

replace SSBNs once the number of warheads per SLBM falls below five (as it would have

under START-II). 16 This points to a future shift away from SSBNs that will be discussed

below.

Connecting the Present to the Future

What remains, therefore, is to bridge the gap between now and then, going from

deterrence by counterforce with our current triad, to minimum deterrence provided with only

a survivable deterrent. If we choose to wait for the reductions to come from the slow pace of arms control negotiations, we are likely to continue on a path of acquiring replacement

systems that become less and less cost-effective. As previously demonstrated, eventually the

numbers of weapons will render strict counterforce unworkable. When that happens the U.S.

will shift, by necessity, to some other deterrent strategy, the best option for which is

minimum deterrence as discussed above. The question is, do we let smaller numbers drive

the change in strategy, or do we shift strategy now and change forces to match?

There are two paths the U.S. can follow to a future which is certain to contain fewer

nuclear weapons and delivery vehicles. The first continues the slow and measured pace of

disarmament begun with the SALT process in the 1970s. Weapons and launchers are

decreased in number in a lock step fashion with Russia. The slow pace of reductions will

likely mean many platforms are kept, and probably replaced, long past when they cease to be

cost-effective. This slow pace also fails to demonstrate a meaningful commitment to

disarmament that the super powers committed to under the Non-Proliferation Treaty (NPT). 17

The second, better path takes the initiative, saves significant money, and demonstrates

8


10/17

U.S. leadership in the disarmament process. As China has demonstrated, smaller numbers

can successfully deter the Russians (and the U.S. for that matter) without the need for

negotiated arms control. Taking this path, the U.S. shifts to minimum deterrence and can

immediately proceed to reduce its numbers unilaterally. 18 The first step is the inactivation of

all silo-based ICBMs. This is an immediate reduction of 25% of deployed warheads.

ICBMs are tempting targets that encourage counterforce targeting, large numbers of weapons

on both sides, and the launch on warning status that provides the best chance for an

inadvertent launch. Launch on warning also prevents U.S. development and use of

conventionally armed ballistic missiles out of concern that such launches could bemisinterpreted as nuclear attacks. 19 Elimination of nuclear armed ICBMs thus removes

several concerns and vulnerabilities while offering to become a valuable conventional global

strike weapon. The second step is to reduce SSBN numbers from fourteen to eight 20 by

converting six single mission SSBNs to multi-mission SSGNs. 21 This reduces the number of

SLBM warheads by forty percent.

Continuing into the future, pressure against SSBNs will mount. The declining

number of warheads means that an ever increasing percentage of the deterrent carried by

each ship will increase. The risk of having such a large percentage of the nuclear eggs in

each basket will lead to a demand for more baskets, but ultimately the per warhead cost of

replacement SSBNs will become unreasonable. Additionally, as the number of warheads

declines, so eventually will the number of warheads per missile. As previously discussed, at

some point the per warhead cost makes SSBNs cost-prohibitive. Given the number of

weapons currently in service, it is quite probable that the inflection point will tend toward

land-based mobile missiles well before a replacement SSBN is needed in 2029.

9


11/17

For the air part of the triad, nuclear capable aircraft are retained for their conventional

capabilities. The number of nuclear cruise missiles can be reduced and nuclear gravity

bombs eliminated. The warheads from the cruise missiles are light weight by design, and

may be useful in the land-based mobile missiles to be fielded later.

The cost savings realized by nuclear force reductions can go straight to conventional

forces. Since World War II, nuclear forces have been used for just one purpose: to deter their

use. Conventional forces have been far more useful.

But while cost savings and reduced numbers are tangible gains, perhaps the biggest

benefit from unilateral reductions is the demonstration of world leadership. Russia and theU.S. have been criticized for not doing enough to reduce nuclear weapons as required by

Article VI of the NPT. 22 China in particular has criticized the slow pace of disarmament,

frequently using this as a lever in a number of disarmament negotiations. The unilateral

reductions discussed above would demonstrate U.S. leadership in this critical area.

Opposing Views

There are many arguments against deep arms reductions, let alone unilateral ones.

One of these arguments is based on technological development and is not so much concerned

with numbers as with new capabilities. The concern is that new Russian and Chinese nuclear

weapons threaten to leave us in a technological backwater. Not only should we not reduce

our current numbers, but we need to advance and modernize our deterrent to keep pace. This

argument is flawed on several counts. First, modernization of the nuclear force is said to

enhance its flexibility. What is implied, but never stated, is that low yield nuclear weapons

will be more usable than big ones. Being usable at all, let alone 'more usable,' requires

abandoning the international norm against nuclear weapons usenot a precedent the U.S. is

10


12/17

likely to break. Second, it is only this usability argument that leads to the conclusion that a

new Chinese (or Russian) warhead is somehow more dangerous than an existing one. A new

'super warhead' developed by Russia does not in any way make our warheads less lethal. The

warhead technology gap is but the latest example of fear mongering, reminiscent of the

missile gap arguments of the Cold War. 23 It was previously pointed out that technology has

changed deterrence significantly on two occasions. Technology may do that again, but

advances in warhead design are not heralds of that kind of change.

A second, more subtle argument is that anything other than counterforce doctrine is

seen as requiring the targeting of civilians, something that has been distinctly out of theinternational norm since World War II. As such, once technology allowed shifting away from

countervalue, the U.S. took the moral high ground and ceased targeting of cities. There are

two answers to this moral and emotional critique. First, as discussed above, accuracy now

allows countervalue to hold something at risk other than cities. Second, it is intellectually

dishonest to claim the use of wide spread counterforce strikes will somehow save lives over

other targeting strategies. After all, many valid industrial and military targets around the

world are in close proximity to population centers. Counterforce may salve the conscience,

but it was never intended as a way to kill fewer people, and arguing otherwise is sophistry.

Finally, the real meaning of this argument, that the moral high ground is best kept by being

the side with the largest amount of WMD, is not only oxymoronic but morally indefensible.

Conclusion

Past assessments by the U.S. concluded that only deterrence by denial would be

effective against the Soviets, and this resulted in a need to disarm in tandem with them.

Separating the U.S. from a denial strategy removes the need for such tandem reductions, and

11


13/17

adopting a strategy of minimum deterrence allows unilateral and large reductions in nuclear

weapons. While the National Security Strategy (NSS) of 2006 states Our deterrence

strategy no longer rests primarily on the grim premise of inflicting devastating consequences

on potential foes, 24 the U.S. continues to have largely the same nuclear forces as it did in

1992. The new U.S. deterrent strategy described herein would truly back away from the

'grim premise,' and it would free resources for the conventional aspects of the new triad

envisioned by the NSS.

Budgetary constraints are not the sole factor influencing a reduction in U.S. nuclear

forces, but substantial resources are committed to a number of nuclear forces that areunnecessary for U.S. security. A review of the past and current security environment

indicates that a revised strategy of minimum deterrence can be implemented that not only

provides security, but also cuts the number of deployed nuclear weapons and significantly

reduces the resources required to field those weapons.

12


14/17

Notes.

1. The concept of a minimum (also called finite) deterrent was first championed by thenCNO ADM Arleigh Burke. These arguments were defeated by the USAF and Secretary of Defense McNamara. See "How Much is Enough?: The U.S. Navy and Finite Deterrence",

George Washington University archives.http://www.gwu.edu/~nsarchiv/nukevault/ebb275/index.htm (accessed 2 September 2009)

2. Although the arguments in this paper are not repeats of previous work, similar discussionsof deterrent theory were used previously in a fall elective paper. See Scott Minium, China's

Nuclear Strategy and What It Means (or Should Mean) to the United States, U.S. Naval War College, 2009.

3. For example, the suspected Israeli deterrent promises its Arab neighbors the punishmentof large scale destruction if the existence of Israel is seriously threatened.

4. Bombers on continuous alert were initially used to provide survivable deterrent sincesubmarine launched missiles did not yet exist.

5. Hans M. Kristensen, Robert S. Norris and Ivan Oelrich, From Counterforce to Minimal Deterrence:A New Nuclear Policy on the Path Toward Eliminating Nuclear Weapons ,Federation of American Scientists Occasional Paper No.7, April 2009, 6.www.fas.org/pubs/_docs/OccasionalPaper7.pdf (accessed 15 December 2009)

6. Depending on how the numbers are counted, SSBNs currently field 50-75% of deployedU.S. nuclear warheads. U.S. Department of State, Bureau of Verification, Compliance, andImplementation, START Aggregate Numbers of Strategic Offensive Arms , (Washington, DC:Department of State, 2008).www.nti.org/e_research/official_docs/dos/dos081001.pdf (accessed 10 Jan 2010)

7. Jeffrey Lewis, The Minimum Means of Reprisal: China's Search for Security in the Nuclear Age (Cambridge, MA: MIT Press, 2007), 30.

8. DongFeng 5 (CSS-4) Intercontinental Ballistic Missile,http://www.sinodefence.com/strategic/missile/df5.asp (accessed 16 October 2009)

9. Lewis, 30.

10. David Kunsman and Douglass Lawson, A Primer On U.S. Strategic Nuclear Policy ,(Albuquerque, NM: Sandia National Laboratories, 2001), 66.

11. Andrew Grotto and Joe Cirincione, Orienting the 2009 Nuclear Posture Review: A Roadmap , (Center for American Progress, November 2008), 24.www.americanprogress.org/issues/2008/11/pdf/nuclear_posture.pdf (accessed 10 October 2009)

13


15/17

12. U.S. Department of State, Bureau of Verification, Compliance, and Implementation,START Aggregate Numbers of Strategic Offensive Arms , (Washington, DC: Department of State, 2008).www.nti.org/e_research/official_docs/dos/dos081001.pdf (accessed 10 Jan 2010)

13. The number and type of missiles is a marginal cost factor for an SSBN. Thus, thenumber of warheads carried by one ship is what makes it cost-effective. As the futurenumber of warheads will doubtless be lower than it is at present, replacing all SSBNs withslightly less ships, but many fewer weapons, makes them very cost-ineffective compared totoday.

14. A full discussion of how minimum deterrent would work is beyond the scope of this paper. For a full analysis of one minimum deterrent option, complete with casualty estimatesand potential target sets, see Kristensen, Norris and Oelrich, From Counterforce to Minimal

Deterrence:A New Nuclear Policy on the Path Toward Eliminating Nuclear Weapons.

15. START-II would have limited SLBM warhead loading to four. See Federation of American Scientists, Strategic Arms Reduction Treaty-II.http://www.fas.org/nuke/control/start2/ (accessed 5 January 2010)

16. For additional information on this conclusion, please see Appendix A.

17. Treaty on the Non-Proliferation of Nuclear Weapons (NPT) 5 March 1970, ArticleVI.

18. Thoughts on unilateral reductions were shaped primarily by the FAS report named aboveand a lecture of opportunity given by Prof Nichols in the fall trimester. The reasoning herein,however, is not derivative. For the FAS report, see Kristensen, Norris and Oelrich, FromCounterforce to Minimal Deterrence:A New Nuclear Policy on the Path Toward Eliminating

Nuclear Weapons .

19. Although use of ICBMs and SLBMs with conventional payloads has been considered,Congress has consistently blocked funding partly due to concerns that Russia could interpretthe launch as a nuclear attack. Of note, since China does not have early warning systemsthey may consider conventional ICBM launches as perfectly reasonable. See ThomasScheber, Conventionally-Armed ICBMs: Time for Another Look, Comparative StrategyVol. 27, no. 4. (July 2008) , 342-343.

20. The 14 SSBNs currently allows four (two per coast) to be underway. Reducing SSBNsto eight will allow two to three to be underway at all times.

21. SSBNs have precisely one mission: strategic deterrence. Attack submarines, in contrast,have a broad variety of peacetime and wartime missions. SSBNs converted to carry largenumbers of cruise missiles become SSGNs, and are capable of performing nearly as many

14


16/17

missions as SSNs, and even a few more.

22. Rear Admiral Eugene Carroll, USN (Ret.), The NPT Review-Last Chance? The Defense Monitor 29, No. 3 (2000), 1-4.

23. Use of fear is a common tactic. For an example, see Mark Schneider, The Future of theU.S. Nuclear Deterrent, Comparative Strategy Vol. 27, no. 4. (July 2008), 345-360.

24. U.S. President, The National Security Strategy, Washington, DC: White House, 2006,22.

15


17/17

Appendix ACost Comparison: SLBM vs Land-based Mobile ICBM

16

missilesSLBM 24 8 $30M 192 1 $3B 3723 194000 nm 12 8 $30M 96 1 $3B 4363 45

24 4 $30M 96 1 $3B 4723 4912 4 $30M 48 1 $3B 4363 91

Land mobile 96 2 $60M 192 96 $5M 6528 346000 nm 48 2 $60M 96 48 $5M 3264 34

48 2 $60M 96 48 $5M 3264 3424 2 $60M 48 24 $5M 1632 34

Assumptions:1. Inertial Nav units cost the same, one per ship, one per land launcher, $3M2. Subs can be built for $3B, land-mobile launchers for $5M3. Missile costs based on current estimates from Federation of American Scientists and extrapolationof Peacekeeper data.4. Land-mobile will be able to carry 2 warheads/miss ile which is feasible with small warheads.5. Personnel costs not considered.

Conclusions:1. Cost of the ship drives SLBM cost, number of launchers drives land-mobile2. Cost of land-based mobile is pay as you go.3. When the number of SLBM warheads falls below 5, time to move ashore.

warheadsper missile

cost per missile

number of warheads

launchersrequired

launcher cost

Total Cost($M)

Cost per warhead ($M)

shifting to minimum deterrence

Documents