On Adapting Nuclear Deterrence - IA de Investigación especializada en el MIT

On Adapting Nuclear Deterrence
to Reduce Nuclear Risk

Brad Roberts

Since the end of the Cold War, changes to the practice of nuclear deterrence by the
United States have been pursued as part of a comprehensive approach aimed at re-
ducing nuclear risks. These changes have included steps to reduce reliance on nuclear
weapons in U.S. defense and deterrence strategies. Looking to the future, los unidos
States can do more, but only if the conditions are right. Policy-makers must avoid
steps that have superficial appeal but would actually result in a net increase in nu-
clear risk. These include steps that make U.S. nuclear deterrence unreliable for the
problems for which it remains relevant.

I n a strategy to reduce nuclear risks, there are many building blocks: formal

and informal arms control, cooperative threat-reduction activities, y estafa-
trols on sensitive materials, tecnologías, and facilities, Por ejemplo. The fo-
cus of this essay is one single building block: the practice of nuclear deterrence by
the United States. In one of their seminal op-eds in The Wall Street Journal, Jorge
Shultz, William Perry, Henry Kissinger, and Sam Nunn made the case in 2011
that reliance on nuclear weapons for deterrence “is becoming increasingly haz-
ardous and decreasingly effective” and called for “a joint enterprise among na-
tions” to work toward “a safer and more stable form of deterrence.”1 Nearly a
decade later, there is little evidence of that “joint enterprise,” as Russia, Porcelana,
and others proved reluctant to join any such effort.2 But what about the Unit-
ed States? How far has it gone toward the envisioned goal? What has the Unit-
ed States done to modify its practice of nuclear deterrence to reduce nuclear risks
and dangers, while ensuring that deterrence remains stable and effective for the
problems for which it remains relevant? How has it accounted for the failure of
the “joint enterprise?” What more should be done? What more can be done in
current circumstances?

T he effort to move away from Cold War approaches in U.S. deterrence

strategy and to adapt deterrence to a changing security environment be-
gan well before the 2011 op-ed and has continued since. Changes to U.S.
nuclear policy and posture have been driven by many factors: the end of Cold

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War confrontation and the desire to consolidate a new political relationship with
Russia, the emergence of new challenges such as nuclear-arming regional pow-
ers and an emergent China, the ambitions of individual leaders to push in certain
directions, and the advocacy of influential individuals and organizations outside
gobierno. Presidents Bill Clinton, George W. Arbusto, and Barack Obama all ar-
rived in office having campaigned in part on the argument that more could and
should be done to move away from Cold War thinking and forces. Each admin-
istration took its own set of steps toward these goals, each with its own framing
contexto: Clinton’s “lead but hedge” strategy, Bush’s “new strategic framework,"
and Obama’s “Prague vision.”3 Each also made decisions to maintain certain nu-
clear forces in the name of strategic stability: eso es, to ensure that no adversary
might be tempted to strike first in a time of war.

This focus on deterrence adaptation spanned the period from the end of the
Cold War in 1990 to the Russian armed annexation of Crimea in 2014. In this pe-
riod, three key developments in the practice of U.S. nuclear deterrence stand out
from a risk-reduction perspective.4

Primero, nuclear deterrence lost its central place in U.S. defense strategy. Esto es
well illustrated by U.S. defense strategy documents. During the Cold War, A NOSOTROS.
secretaries of defense published annual reports to Congress on defense strategy,
in which nuclear issues featured prominently and consistently. In the post–Cold
War era, it is difficult to find even a mention of nuclear issues in the Quadrennial
Defense Reviews. This follows the shift in focus away from the possibility of an
Armageddon-like war with the Soviet Union and onto new contingencies with no
or at most limited nuclear aspects. As the Obama administration’s Nuclear Pos-
ture Review (NPR) put it, nuclear employment might be considered only in “a
narrow range of circumstances” when the vital interests of the United States or an
ally are at risk. The world of 2009 seemed to present no such flash points or path-
ways to wars touching on such vital interests.

Segundo, reliance on non-nuclear means of deterrence increased significantly.
In the 1990s, there was growing recognition of the rising value of missile defens-
es for reinforcing deterrence of regional challengers armed with weapons of mass
destruction (WMD) and long-range missiles. A NOSOTROS. defense planners came to see re-
liance on nuclear deterrence for this problem as unreliable and thus dangerous.
Complementary measures were needed. With the continued maturation of missile
defense technologies, the Congress passed the National Missile Defense Act of
1999, which established that the United States would “deploy as soon as is tech-
nologically possible an effective National Missile Defense system capable of de-
fending the territory of the United States against limited ballistic missile attack
(whether accidental, unauthorized, or deliberate).”5 President Clinton’s succes-
sors went even further in developing non-nuclear means. El 2001 George W. Arbusto
administration’s NPR expressed a commitment to move toward a “new triad” of

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Dédalo, la Revista de la Academia Estadounidense de las Artes & SciencesOn Adapting Nuclear Deterrence to Reduce Nuclear Risk

offensive strike forces (including nuclear, non-nuclear, and nonkinetic means),
ballistic missile defense, and a responsive infrastructure. The Obama administra-
tion continued the effort to rebalance the deterrence portfolio by strengthening
regional deterrence architectures comprehensively, in a manner that embedded a
“tailored nuclear component” in an approach encompassing an intended “favor-
able balance” of conventional forces, regional missile defenses, limited homeland
missile defenses, plus resilience in cyberspace and outer space.

Tercero, the practice of U.S. nuclear deterrence adapted to the more multipo-
lar character of the present international system by becoming more flexible and
“tailored.” In the bipolar context of the Cold War, the United States developed
an approach to nuclear deterrence aimed at being able, in times of crisis and war,
to put at risk what Soviet leaders valued. A deterrence strategy premised on be-
ing able to threaten what enemy leaders value must be sufficiently flexible to con-
tend with a changing cast of such leaders with a changing constellation of val-
ues and interests. Respectivamente, each post–Cold War administration has praised
the virtues of a more “tailored approach” to deterrence for a more complex secu-
rity environment. The George W. Bush administration formally abandoned the
long-standing Single Integrated Operational Plan in 2003 in favor of a more flex-
ible approach. That new approach gives the president a wider set of options for
the employment of both nuclear and non-nuclear weapons, a wider set of poten-
tial objectives, and the ability to adapt plans quickly to cope with rapidly chang-
ing circumstances.6 The Obama administration continued this focus on tailor-
ing deterrence for the range of challenges present in the security environment. En
its employment guidance, it focused on “more likely 21st century contingencies,"
as opposed to a major bolt-out-of-the-blue attack by a nuclear peer or near peer.7
Each administration has also relied on the enduring strategy of ensuring that any
country capable of posing an existential threat to the United States never comes to
a point of seriously contemplating such an attack.

T hese three changes were aimed at “a safer and more stable form of deter-

rence.”8 They did so by reducing the risk that the United States might rely
on nuclear deterrence even when its nuclear threats might not be credible.
In parallel, the post–Cold War administrations have made decisions to maintain
some elements of continuity with prior practice. Three such continuities stand
out in the debate about risk reduction.

The first was the preservation of what the Obama administration called “the
fundamentals of deterrence.” In a June 2013 report to Congress on its nuclear de-
terrence strategy, the administration described these as:

•

“The fundamental role of nuclear weapons is to deter nuclear attack on the
United States and its allies and partners.”

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149 (2) Spring 2020Brad Roberts

•

“The United States will only consider the use of nuclear weapons in ex-
treme circumstances to defend the vital interests of the United States or its
allies and partners.”

“The United States will maintain a credible nuclear deterrent capable of
convincing any potential adversary that the adverse consequences of at-
tacking the United States or our allies and partners far outweighs any po-
tential benefit they may seek to gain from such an attack.”

“U.S. policy is to achieve a credible deterrent, with the lowest possible
number of nuclear weapons, consistent with our current and future securi-
ty requirements and those of our allies and partners.”

“All plans must also be consistent with the fundamental principles of the
Law of Armed Conflict. Respectivamente, plans will, Por ejemplo, apply the
principles of distinction and proportionality and seek to minimize collat-
eral damage to civilian populations and civilian objects. The United States
will not intentionally target civilian populations or civilian objects.”9

A second element of continuity was the commitment to prepare for the possi-
bility that deterrence might fail. Even in a security environment in which the pros-
pects of nuclear conflict seem extremely remote, the potential costs of being un-
prepared for a failure of deterrence were deemed too high. Each president in the
post–Cold War period has faced the unhappy facts that 1) there exists a small but
troubling set of foreign leaders deeply hostile to U.S. interests and to the regional
orders and allies the United States seeks to protect; 2) such leaders are armed with,
or are pursuing, nuclear or other weapons of mass destruction and the means to
deliver them at long range; y 3) even tailored deterrence may prove unreliable
in deterring nuclear aggression by leaders whose values and interests are funda-
mentally different from those of the United States and its allies.10

Such preparations include ready forces capable of operating at both the re-
gional and strategic level, forces capable of operating under attack and reaching
their target, the development of employment options for the president, and exer-
cises of the forces, the planning process, and the deliberative process. Such readi-
ness lends credibility to the threat of U.S. nuclear retaliation. It has the additional
value of helping to negate the potential coercive value of enemy nuclear threats by
robbing them of their credibility.

This commitment to prepare for deterrence failures implies a rejection of min-
imum deterrence, the third major element of continuity. Minimum deterrence is
a mode of deterrence that does not particularly concern itself with the necessary
and appropriate responses if deterrence fails. The advocates of minimum deter-
rence for the United States have argued that “deterrence today would remain sta-
ble even if retaliation against only ten cities were assured.”11 This might be so. Pero

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Dédalo, la Revista de la Academia Estadounidense de las Artes & SciencesOn Adapting Nuclear Deterrence to Reduce Nuclear Risk

it might not, if a vital national interest were at risk. Minimum deterrence makes
no effective accommodation for the principles of discrimination and proportion-
ality or for a theory of deterrence that depends on putting at risk only those things
most valued by an enemy leadership. It promises simple, crude punishment of an
enemy society.12

These continuities reflect the fact that nuclear deterrence itself is a form of risk
reducción. It reduces the risk of nuclear-backed aggression and nuclear employ-
ment in war and thus helps preserve the nuclear taboo. It also reduces the coer-
cive value of nuclear threats. Until such time as humankind discovers the means
to safely eliminate nuclear weapons, nuclear deterrence must remain effective for
the problems for which it remains relevant. This requires leadership focus on de-
terrence strategy, a commitment to excellence in the practice of deterrence, clear
signals of resolve to defend vital interests, and the associated capabilities.

I t is useful also to recall the risk-reduction policy options that were considered

but rejected in this period. In the Obama administration, al menos, había
a sustained and thorough exploration of options. Policy-makers were inter-
ested in three main questions: Would the proposed measure reduce real risk in a
material way? Would it have unintended effects that might increase risk? Qué
would be the net impact on nuclear risk? This risk framework was familiar to se-
nior policy-makers; as the administration argued in 2010, “defense strategy re-
quires making choices: accepting and managing risk is inherent in everything the
Departamento [of Defense] does.”13

De-alerting, Por ejemplo, had many advocates outside the administration.
Whether to take additional steps to reduce the alert status of U.S. nuclear forces is
an obvious first-order question for nuclear risk reduction. The case for doing so is
that it would reduce the risk of accidental and unauthorized use because it reduc-
es the ability to rush a decision in the context of imperfect information. But most
officials were not persuaded that that risk is significant. There is also no reason
to think that current Russian leadership would join such an effort, not least be-
cause it would disproportionately affect the Russian force (given the higher per-
centage of its deterrent associated with land-based systems). Whatever the bene-
fit might prove to be in practice, this must be weighed against the risk of a compet-
itive re-alerting in time of crisis. A nuclear variant of August 1914 looks especially
unappealing to senior policy-makers. De este modo, further de-alerting was rejected in the
2010 NPR. But a rushed and imperfect decision on nuclear employment is also un-
appealing, so the Obama administration put its emphasis on improving support
to the president in preparing for and making such decisions.

Another risk reduction option advocated by nongovernmental experts was nu-
clear no-first-use (NFU). The case for adopting a policy of NFU is that it would re-
duce the instability in crisis generated by concerns about the need to use-or-lose

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149 (2) Spring 2020Brad Roberts

nuclear forces. The potential unintended consequence is that a WMD-armed ag-
gressor might be emboldened to challenge by non-nuclear means a vital interest
of the United States or, more likely, a U.S. ally. The administration saw this risk
as material and thus rejected NFU (and the closely related “sole purpose” formu-
lación).14 But to help underscore the last-resort character of possible U.S. nucle-
ar employment, the Obama administration emphasized that such employment
would be considered only in “extreme circumstances.”

The Obama administration also considered changes to the U.S. nuclear pos-
ture in the name of risk reduction. These included, Por ejemplo, the possible re-
tirement of forward-based nuclear-capable fighter-bombers in Europe (deployed
there in support of NATO’s unique nuclear sharing arrangements). The case for
retirement is that it would reduce the risk of theft or accidents. De nuevo, there seems
little prospect that Russia would join in such an effort (having rejected it consis-
tently for many years). The case against it is that it might embolden Russian chal-
lenges to NATO and encourage Russian nuclear escalation in conflict. At a time of
uncertainty and rising concern about Russian military ambitions in Europe, el
Obama administration concluded that the case for retaining the fighter-bombers
outweighed the case for retirement. The administration viewed these capabili-
ties as essential to the demonstration of the alliance’s promise that an attack on
any NATO ally will be treated as an attack on all and, En particular, that any nucle-
ar attack on a NATO ally will implicate all those participating in NATO’s sharing
arrangements. These NATO sharing arrangements also serve as a unique link be-
tween the United States and its allies in both Europe and Asia by demonstrating
for all the nuclear risks it is willing to run to safeguard allied vital interests. Estos
efectos, también, are good for deterrence.

Retirement of the ICBM (intercontinental ballistic missile) force was also oft
debated. The risk-reduction case for retirement is that it would reduce the risk of
accidental launch.15 The case against it is that retirement would erode the credibili-
ty of U.S. nuclear threats. The ICBM force lends credibility to U.S. nuclear threats in
two ways. A successful strike on four-hundred-plus nuclear targets must look vast-
ly more challenging to a leader contemplating nuclear war with the United States
than a preemptive strike on the relatively few critical aim points that would remain
if the ICBM silos were gone. With a large U.S. target base, only one country can con-
template a possibly successful disarming strike; without that base, more countries
could do so. Además, a massive strike at targets spread across the American heart-
land would seem to ensure retaliation by a deeply wounded nation. These effects
are good for deterrence. Respectivamente, the Obama administration committed to the
modernization of all three legs of the nuclear triad, as has the Trump administration.
En suma, the period from 1990 a 2014 was marked by a few key developments
en los EE.UU.. practice of nuclear deterrence that helped to reduce nuclear risk. Pero
the “fundamentals of deterrence” remained because deterrence itself remained

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Dédalo, la Revista de la Academia Estadounidense de las Artes & SciencesOn Adapting Nuclear Deterrence to Reduce Nuclear Risk

relevant in this period, albeit in a reduced and different role. Además, A NOSOTROS.
planners considered and rejected various new forms of risk reduction as, on bal-
ance, contributing more risk than they might eliminate.

T hen came the revelations of 2014. President Vladimir Putin proved will-

ing to use military force to change international borders. He promised to
“snap back hard” against a European security order he deemed unjust and
dangerous. And he called for “new rules or no rules” for a global order he saw as
dominated by a United States seeking “absolute security” (eso es, security for the
United States at everyone else’s expense). These revelations cast a bright light on
his nuclear strategy: Putin had given nuclear weapons a central place in his strat-
egy for Russian renewal, nuclear threats a central place in his political strategy for
coercing NATO, and limited nuclear war a central place in his military strategy.
This raised basic policy questions for the United States and its allies about wheth-
er and how to further pursue nuclear risk-reduction strategies.

In retrospect, it is clear that the world should not have been surprised in 2014.16
Already in the 1990s, the Russian military began to debate how to respond to the
emerging American way of waging war. In the early 2000s, Putin, as the new Rus-
sian president, supported investments in Russian nuclear forces, in part as com-
pensation for weaknesses in Russian general purpose forces. But his incentives and
objectives appear to have shifted over time. His worldview evolved substantially
de 2001 a 2014: from his effort to “reset” relations with the United States after
9/11, to his plaintive call in 2007 for renewed cooperation amidst frustration with
American “hyper use of force,” to his 2014 watershed decisions and declarations.
In line with this shift in President Putin’s perspective, the Russian military en-

acted dramatic changes in policy, posture, and behavior. Por ejemplo:

•

• Following Putin’s February 2007 speech to the Munich security confer-
ence, Russia launched a campaign of harassment against its neighbors that
included crippling cyberattacks (against Estonia, Por ejemplo) and re-
newed long-range bomber patrols and mock nuclear strikes on Western
capitals.17
In this period, Russia also suspended compliance with the Treaty on Con-
ventional Forces in Europe and violated the Treaty on Intermediate-Range
Nuclear Forces. Selective compliance with the Open Skies Treaty followed,
along with Russian violations of multiple other arms control and military
transparency agreements.18
En 2008, Russia intervened militarily in Georgia. Shortcomings in Russian
military performance galvanized a major effort finally to reform and mod-
ernize fully the Russian military institution and its capabilities. En 2009,
it restarted its ZAPAD exercise series to test and demonstrate its ability to

•

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149 (2) Spring 2020Brad Roberts

conduct large-scale military campaigns, including using strategic forces, en
a major regional war on its western flank.

•

En 2012, Russia announced a major adjustment to its force modernization,
aimed at ramping up a diverse set of new capabilities, both strategic and
nonstrategic.19 Somewhere in this period, President Putin also initiated the
development of the novel strategic weapons that would be revealed in 2018.
Some of the results were publicized in spring 2019 by Defense Minister
Sergei Shoigu, who reported an increase from 2013 in the number of carri-
ers of high-precision long-range weapons on land, mar, and in the air by a
factor of twelve and in the number of high-precision cruise missiles (todo
which are dual-capable) by a factor of thirty.20 The Russian military also
made qualitative and quantitative improvements to its tactical nuclear
forces and increased the role for low-yield options.21

• Apparently also in this time frame, Putin made the decision to interfere di-
rectly and illicitly in the domestic politics of Western countries, incluido
el 2016 A NOSOTROS. presidential election.22

• Russia published updates to its foreign policy concept and military doc-
trine in 2013 y 2014, respectivamente, setting out the principles of a more con-
frontational approach to the U.S.-led world order and the strategy of “ac-
tive defense.”23
En 2014, Putin authorized the military to invade Ukraine and, later through
referendum, annexed Crimea, using force to alter international borders in
Europe and violating a central norm of international behavior.

•

• By 2015, Putin had taken steps to demonstrate what he meant by “no rules”
(or perhaps demonstrate the new rules themselves) with direct interfer-
ence in the political affairs of other states, targeted extraterritorial killings,
direct military assistance to a thuggish Syrian regime, and multiple other
efforts to undermine Western institutions, valores, and leaders.

One result of this string of developments is a new Russian approach to region-
al war involving rapid power projection, integrated defensive and offensive op-
erations in aerospace, and the use of all means available to influence the strategic
calculus of the enemy, including kinetic and nonkinetic weapons as well as nucle-
ar and non-nuclear strategic options. It is a strategy intended to present the ene-
my with unacceptable risks of escalation by any of these means and thus to drive
the costs of conflict with Russia (or continued conflict) beyond the enemy’s stake.
It is a strategy of deterrence built on the foundations of coercion through black-
mail and brinkmanship backed up by a credible threat to employ all these means.
Surveying this history, some Western analysts have concluded that there has
been little or no change in the nuclear threat posed by Russia and that President

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Dédalo, la Revista de la Academia Estadounidense de las Artes & SciencesOn Adapting Nuclear Deterrence to Reduce Nuclear Risk

Putin conceives a “predominantly defensive” role for nuclear weapons aimed at
deterrence, not coercion or war-fighting.24 Some argue further that the U.S. política-
makers have misunderstood and/or misrepresented the “escalate to de-escalate”
strategy and that Russian leaders are not prepared to employ nuclear weapons
early in a conflict to seek prompt war termination on their terms.25

Already in the Obama era, NATO leaders had come to different conclusions
about these risks. At NATO summits in Wales and Warsaw, they made it clear that
they see these developments as dangerous and destabilizing and as requiring en-
hancements to the alliance’s overall deterrence and defense posture, to its nuclear
readiness, and to its nuclear forces. These enhancements are aimed at “addressing
potential adversaries’ doctrine and capabilities” in order to ensure that NATO’s
deterrence posture remains “credible, flexible, resilient, and adaptable.”26

In the United States, the renewal of focus on Russia as an object of U.S. de-
terrence strategy began in 2015 with Secretary of Defense Ash Carter’s call for “a
new playbook for Russia.”27 In its final year, the Obama administration reject-
ed any further unilateral changes to U.S. nuclear policy and posture in support of
the Prague vision in part because of the need for deterrence confidence vis-à-vis a
more dangerous Russia (and a more assertive China). But it fell to the newly elect-
ed Trump administration to put together that new playbook.

T o what extent is the nuclear deterrence strategy of the Trump administra-

tion a departure from past practice? Like its predecessors, the Trump ad-
ministration has embraced “the fundamentals of deterrence,” planned for
the possibility that deterrence might fail, and rejected minimum deterrence. También
like its predecessors, it has sought to increase the role in deterrence of non-nucle-
ar means such as missile defense and hypersonic non-nuclear strike capabilities,
to tailor deterrence to diverse challengers, and to strengthen extended deterrence.
On the central issue of the role of nuclear weapons, the Trump administration
has been more ambiguous. Por un lado, its NPR reiterates the limited roles
set out in the 2010 NPR; en el otro, it explicitly opens the door to nuclear deter-
rence of catastrophic cyberattacks.

To deal more directly with the new Russian challenge, the Trump administra-
tion might have changed deterrence strategies or sought new nuclear weapons
with new military purposes. En cambio, it chose to focus on supplementing the de-
terrence toolkit with additional reduced-yield options. It also sought to ensure an
enduring ability to deliver reduced-yield weapons past steadily improving Rus-
sian air defenses. In this way, the administration hopes to redress any doubts lead-
ers in Moscow might have about the capability and resolve of the United States
and NATO to defend their interests by all necessary means. This is intended to
buttress deterrence and negate nuclear coercion by Russia and thereby raise the
nuclear threshold.

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149 (2) Spring 2020Brad Roberts

But some critics see a substantial change in deterrence strategy: a shift to nu-
clear war-fighting that necessarily lowers the nuclear threshold. To assess this ar-
gument, a Cold War context is needed. What did it mean to the nuclear planners
of that era to be prepared to fight a nuclear war successfully? In NATO’s flexible
response doctrine, it meant being prepared to employ nuclear weapons in signif-
icant numbers at the tactical level of war to enable the defeat of numerically su-
perior Warsaw Pact ground and air forces. De este modo, the United States and NATO de-
ployed thousands of nuclear artillery shells and land mines. Deterrence was sup-
ported by preparations to fight at any level of nuclear scope and intensity that the
Soviet leadership might choose. To prevail meant to achieve military objectives
at the tactical and operational levels and to survive the war with some objectives
achieved and interests intact despite the employment of nuclear weapons by both
sides in support of their military operational objectives.

This is not how U.S. military planners have thought about potential nuclear con-
flict in the post–Cold War era. They have not prepared for the employment of nu-
clear weapons for tactical benefit. De hecho, the United States brought home and de-
stroyed its tactical nuclear weapons (the remaining reduced-yield capability–the
nuclear bomb–can be used to support tactical, theater, or strategic goals). Bastante,
it has prepared for the possible employment of nuclear weapons at the strategic and
theater levels of war, incluido, on a very limited basis, to shape the enemy’s intent
and capability to sustain war. The purpose of such employment would be to termi-
nate rapidly the nuclear phase of war or otherwise negate a threat to a vital interest.
To achieve this effect, the enemy must be compelled to reassess the assump-
tions that led to their decision to employ nuclear weapons or otherwise jeopardize
a vital interest. Such a decision would likely only be made by the enemy on the as-
sumption that the United States would not respond to nuclear attack, especialmente si
limited in nature, or would not respond in a manner as to impose significant cost or
new risk for the attacker. To alter the enemy’s calculus of benefits, costos, and risks,
the United States must be capable (and must be seen as capable) of limited nucle-
ar retaliation to achieve effects the enemy would see as costly, whether militari-
ly or politically. It must also be seen as capable of further nuclear employment in
more damaging ways. It need not be seen as capable of engaging in extended and
large-scale nuclear exchanges at the tactical, operational, and strategic levels of a
regional war. De este modo, each administration since the end of the Cold War has chosen
to maintain the capability to forward-deploy a limited number of nuclear bombs
with forward-based fighter-bombers, as opposed to strategic delivery systems.

The Trump administration’s pursuit of supplemental low-yield capabilities is
consistent with this approach to deterrence as it has evolved since the Cold War.
Deployment of these capabilities would help to reinforce NATO’s message that it
has the means and resolve to defend its interests by all means necessary–at a time
when these appear to be in some doubt in Moscow.

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Dédalo, la Revista de la Academia Estadounidense de las Artes & SciencesOn Adapting Nuclear Deterrence to Reduce Nuclear Risk

I n an era when the hoped-for “joint enterprise” with Russia and China has

proven beyond our reach, what more can and should the United States do to
adapt its practice of nuclear deterrence to reduce nuclear risks?
Part of the answer is to continue working on that joint enterprise while accept-
ing that the near-term payoffs may be few and the long-term payoffs uncertain.
Administrations should focus on the ongoing dialogue among the five permanent
members of the UN Security Council, who bring shared interests to this process.28
Such a joint enterprise should also include a renewal of bilateral, trilateral, y
multilateral arms control for new purposes.

Part of the answer is to update the menu of potential options for reducing risk
in light of the risk net assessment framework described above.29 The advocacy
community on risk reduction loses credibility every time it readvocates in a one-
sided way for an approach rejected by even sympathetic policy-makers.

And part of the answer is to focus on emerging nuclear risks. In both Europe
and Northeast Asia, the strategic balance has shifted in ways unfavorable to de-
terrence at the conventional level of war and in the new domains of cyberspace
and outer space. This increases crisis instability. In the strategic postures of Rus-
sia, Porcelana, y los estados unidos, capabilities in the new domains are increasing-
ly salient, as is competition in these domains and in the more familiar offense-
defense realm (with new competition for hypersonic delivery systems, for exam-
por ejemplo). This increases strategic unpredictability and arms race instability. These new
instabilities bring new forms of nuclear risk. From a U.S. policy perspective, allá
are important questions about the possibility of reducing the risks of both crisis
and arms race instability by encouraging restraint. Some of those questions relate
to what might be accomplished cooperatively with Russia and/or China; otros
relate to what must be accomplished cooperatively with U.S. allies and partners.
In defining these new risks and developing strategies to mitigate them, los unidos
States must continue to balance the need to minimize risk with the need to ensure
that deterrence remains a viable risk-reduction strategy.

F or most of the period since the Cold War, changes to the U.S. practice of nuclear

deterrence have contributed to a comprehensive strategy to reduce nuclear
risks by reducing reliance on nuclear threats where they may lack credibility.
Current prospects for more such adaptations, sin embargo, are not good. Most of the ad-
vances were harvested in the period from 1991 a 2014. In an eroding security envi-
ambiente, the most likely gains in nuclear risk reduction will be in deterring threats
rather than reducing or eliminating them. In current circumstances, there appears to
be no immediate prospect that Russia and China (or North Korea and other nuclear-
weapon states) will join in a collective effort to remake the deterrence framework
on a fundamental level. Their embrace of nuclear weapons to protect themselves, en
large measure against the exercise of U.S. fuerza, appear deep and enduring.

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149 (2) Spring 2020Brad Roberts

In this context, the only fundamental adaptations to the practice of deter-
rence that are possible for the United States are unilateral in character. These have
sometimes had value. But many such measures have been rejected–repeatedly–
as contributing to a net increase, as opposed to a net decrease or elimination, de
nuclear risk. Al mismo tiempo, there may be more limited opportunities to address
the crisis and arms race instabilities of today’s deterrence relationships. But even
while exploring new possible threat reduction measures, the United States and its
allies must ensure that deterrence remains effective for the problems for which it
is relevant, albeit with a posture of restraint so as not to stimulate unwanted re-
sponses by others.

nota del autor

The author is grateful for constructive feedback on earlier drafts of this essay from
fellow contributors to this issue of Dædalus and from Austin Long, Frank Miller,
and Larry Welch. The views expressed here are the personal views of the author
and should not be attributed to any other source.

Sobre el Autor

Brad Roberts is Director of the Center for Global Security Research at the Law-
rence Livermore National Laboratory in California. From April 2009 to March
2013, he was Deputy Assistant Secretary of Defense for Nuclear and Missile De-
fense Policy, in which role he served as Policy Director of the Obama administra-
tion’s Nuclear Posture Review and Ballistic Missile Defense Review. He is the au-
thor of The Case for U.S. Nuclear Weapons in the 21st Century (2015) and has recently pub-
lished in Bulletin of the Atomic Scientists and The Washington Quarterly.

notas finales

1 George P. Shultz, William J. Perry, Henry A. Kissinger, and Sam Nunn, “Deterrence in the

Age of Nuclear Proliferation,” The Wall Street Journal, Marzo 7, 2011.

2 For a discussion of the Obama administration’s effort to engage Russia and China in a
remaking of the nuclear deterrence framework, see Brad Roberts, “On Creating the
Conditions for Nuclear Disarmament: Past Lessons, Future Prospects,” The Washington
Quarterly 42 (2) (2019): 7–30.

3 For a detailed discussion of these frameworks and their nuclear policy implications, ver
Brad Roberts, “The Evolution of U.S. Nuclear Policy and Posture,” in The Case for U.S.
Nuclear Weapons in the 21st Century (stanford, California: Stanford University Press, 2015),
cap. 1, 11–50.

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4 Except as noted, all references in this section are from the Nuclear Posture Reviews con-
ducted by the Clinton, Arbusto, and Obama administrations. Note that the George H. W..
Bush administration did not conduct an NPR as such, though it did review and make
extensive changes to U.S. nuclear policy and posture. Note also that the Obama ad-
ministration was the first to release an actual NPR report. The Clinton administration
reported out the results of the inaugural NPR (conducted in 1994) as a chapter in the
then-annual Report of the Secretary of Defense to the President and the Congress. Ver
“Nuclear Posture Review,” in William J. Perry, Report of the Secretary of Defense to the Pres-
ident and the Congress (Washington, CORRIENTE CONTINUA.: A NOSOTROS. Oficina de Imprenta del Gobierno, 1995). El
George W. Bush administration conducted an NPR in 2001 and prepared both classi-
fied and unclassified versions, though the former leaked and thus the latter could not
be approved for release. The record therefore consists of “United States Department
of Defense Briefing Slides,” January 9, 2002; Donald H. Rumsfeld, "Prefacio,” Nuclear
Posture Review (Washington, CORRIENTE CONTINUA.: A NOSOTROS. Department of Defense, 2002); Donald H.
Rumsfeld, Annual Report to the President and the Congress (Washington, CORRIENTE CONTINUA.: Office of the
Secretary of Defense, 2003); and Douglas J. Feith, “Statement before the Senate Armed
Services Committee Hearing on the Nuclear Posture Review,” February 14, 2002. Ver
also Keith B. Payne, “The Nuclear Posture Review: Setting the Record Straight,” The
Washington Quarterly 28 (3) (2005): 135–151; and Keith B. Payne, “The Nuclear Posture
Review and Deterrence for a New Age,” Comparative Strategy 23 (4/5) (2004). Además,
late in the George W. Bush administration, the secretaries of defense and energy at-
tempted to renew momentum around the main objectives of the 2001 NPR with an un-
classified report on nuclear deterrence (the Gates-Bodman Report). See National Security
and Nuclear Weapons in the 21st Century (Washington, CORRIENTE CONTINUA.: A NOSOTROS. Department of Defense
and U.S. Departamento de Energía, 2008). The Obama administration released not only
its NPR report, but also an unclassified report to Congress characterizing the new nu-
clear employment guidance issued by President Obama to the U.S. military at the same
tiempo. See Report on Nuclear Employment Strategy of the United States, Specified in Section 491 de 10
USC. (Washington, CORRIENTE CONTINUA.: The White House, 2013). The Trump administration’s NPR
was issued in 2018, but at the time of writing, there has been no detailed elaboration of
the internal debates underpinning the policies chosen.

5 Greg Thielman, “The National Missile Defense Act of 1999,” Arms Control Today, Julio 8,

2009.

6 Paul I. bernstein, “Post-Cold War U.S. Nuclear Strategy,” in On Limited Nuclear War in the
21st Century, ed. Jeffrey A. Larsen and Kerry M. Kartchner (stanford, California: stanford
Prensa universitaria, 2014), 89.

7 Report on Nuclear Employment Strategy of the United States.

8 Recalling Schultz et al., “Deterrence in the Age of Nuclear Proliferation.”
9 Ibídem., 3–4.
10 Ver, Por ejemplo, ibid., 2.
11 Bruce Blair, Victor Esin, Matthew McKinzie, et al., “Smaller and Safer: A New Plan for

Nuclear Postures,” Foreign Affairs 89 (5) (2010): 10.

12 Keith B. Payne and James Schlesinger, Minimum Deterrence: Examining the Evidence (Fairfax,

Va.: National Institute for Public Policy, 2013).

13 A NOSOTROS. Department of Defense, Quadrennial Defense Review Report, 2010 (Washington, CORRIENTE CONTINUA.:

A NOSOTROS. Department of Defense, 2010), 89.

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149 (2) Spring 2020Brad Roberts

14 Brad Roberts, “Re-Debating Nuclear No First Use, De nuevo,” Survival 61 (3) (2019).
15 William J. Perry, “Why It’s Safe to Scrap America’s ICBMs,"El New York Times, Septem-

ber 20, 2016.

16 This summary is drawn from “The Second New Problem: Relations with Putin’s Rus-
sia,” in Roberts, The Case for U.S. Nuclear Weapons in the 21st Century, cap. 4, 106–140. Ver
also Angela Stent, Putin’s World: Russia against the West and with the Rest (Nueva York: Twelve,
2019).

17 Matthew Bodner, “Russia’s Strategic Bomber Fleet on Global Intimidation Drive,” The
Moscow Times, Marzo 19, 2015. These flights violated a 1991 signed agreement with the
United States and the United Kingdom.

18 See the U.S. Department of State annual reports on Adherence to and Compliance with Arms
Control, Nonproliferation, and Disarmament Agreements and Undertakings (Washington, CORRIENTE CONTINUA.:
A NOSOTROS. Department of State, various years).

19 See the May 2012 announcement of President Putin’s decision to develop and implement

a force development Plan of Action by 2020 on a year-by-year basis.
20 “Pivotal Changes in Russian Forces,” Red Star online, Marzo 16, 2019.
21 See Defense Intelligence Agency, Russian Military Power: Building a Military to Support Great
Power Aspirations (Washington, CORRIENTE CONTINUA.: Defense Intelligence Agency, 2017), 29–31; “Ev-
idence of Russian Development of New Subkiloton Nuclear Warheads [Redacted],"
Intelligence Memorandum, Office of Transnational Issues, Central Intelligence Agen-
cy, Agosto 30, 2000, approved for release October 2005, https://www.cia.gov/library/
readingroom/docs/Doc_0001260463.pdf; and Jacob W. Kipp, “Russia’s Nonstrategic
Nuclear Weapons,” Military Review, May–June 2001, https://www.hsdl.org/?abstract
&did=3693.

22 Central Intelligence Agency, Federal Bureau of Investigation, National Security Agency,
Assessing Russian Intentions and Activities in Recent U.S. Elections (Washington, CORRIENTE CONTINUA.: Office of
the Director of National Intelligence, 2017).

23 See Dave Johnson, Russia’s Conventional Precision Strike Capabilities, Regional Crises, and Nucle-
ar Thresholds (Livermore, California: Lawrence Livermore National Laboratory, 2017); Ste-
phen R. Covington, The Culture of Strategic Thought Behind Russia’s Modern Approaches to War-
tarifa (Cambridge, Mass: The Belfer Center for Science and International Affairs, Har-
vard Kennedy School, 2016); Andrei Kokoshin, Ensuring Strategic Stability in the Past and
Present: Theoretical and Applied Questions (Cambridge, Masa.: The Belfer Center for Sci-
ence and International Affairs, Harvard Kennedy School, 2015); and Kristin Ven Bruus-
gaard, “Russian Strategic Deterrence,” Survival 58 (4) (2016): 7–26.

24 Ver, Por ejemplo, Anya Loukianova Fink and Olga Oliker, “Russia’s Nuclear Weapons in
a Multipolar World: Guarantors of Sovereignty, Great Power Status & Más,Dédalo
149 (2) (Primavera 2020).

25 Olga Oliker, “Moscow’s Nuclear Enigma: What is the Russian Arsenal Really For?"
Asuntos exteriores 97 (6) (2018). For the opposing case, see Katarzyna Zysk, “Escalation and
De-Escalation in Russian Military Strategy,” Revista RUSI 163 (2) (2018): 4–22.

26 North Atlantic Treaty Organization, “Warsaw Summit Communiqué,” July 9, 2016,

para. 52, https://www.nato.int/cps/en/natohq/official_texts_133169.htm.

27 Ash Carter, “A Strong and Balanced Approach to Russia,” Survival 58 (6) (2016): 51–62.

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28 See Christopher Ford, The P-5 Process and Approaches to Nuclear Disarmament: A New Structured

Dialogue (Washington, CORRIENTE CONTINUA.: A NOSOTROS. Department of State, 2018).

29 A good starting point would be a menu of options assembled by the United Nations In-
stitute for Disarmament Research. See Wilfred Wan, Nuclear Risk Reduction: The State of
Ideas (Geneva: United Nations Institute for Disarmament Research, 2019).

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149 (2) Spring 2020Brad Roberts
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