www.ndu.edu/inss SF No. 272 1 

In most real conflicts the potential escalation sequence is more like a ladder 

that has been bent and twisted out of shape with all sorts of extra and odd 

protuberances added on, which vitally affect how the conflict does or does not 

climb it. . . . Controlling escalation will depend crucially on identifying the 

particular twists and protuberances of that conflict’s misshapen ladder.1

Warfare has become even more complicated since Richard Smoke wrote 

this description of escalation in 1977. The National Security Space Strategy describes space as “congested, contested, and competitive,” yet satellites underpin 

U.S. military and economic power. Activity in cyberspace has permeated every 

facet of human activity, including U.S. military operations, yet the prospects for 

effective cyber defenses are bleak. Many other actors depend on continued access 

to these domains, but not nearly as much as the United States.

For this reason, some analysts argue that China’s opening salvo in a conflict with the United States would unfold in space and cyberspace. Worst-case 

scenario assessments conclude that such an attack might render the United 

States blind, deaf, and dumb almost exclusively through nonkinetic means, 

although it is unclear how effective attacks in the space and cyber domains 

would be in an actual military conflict. How do concepts such as escalation, 

deterrence, and proportionality apply in such a context? What “odd protuberances” would counterspace and cyber attacks create in an escalation ladder? 

What are the salient thresholds for cross-domain attacks? And what exactly 

does cross-domain mean? This paper explores these questions using the illustrative example of a hypothetical U.S.-China conflict because both countries 

Deterrence and Escalation in 

Cross-domain Operations:

Where Do Space and 

Cyberspace Fit?

by Vincent Manzo

Strategic Forum

National Defense University

About the Authors

Vincent Manzo is a Research Analyst 

in the Center for Strategic Research, 

Institute for National Strategic Studies, 

at the National Defense University. 

Key Points

◆ Many weapons systems and most 

military operations require access 

to multiple domains. These linkages 

create vulnerabilities that actors can 

exploit by launching cross-domain 

attacks; the United States may seek 

to deter such attacks by threatening 

cross-domain responses. However, 

both the U.S. Government and 

potential adversaries lack a shared 

framework for analyzing how counterspace and cyber attacks fit into 

an accepted escalation ladder.

◆ The real-world effects of attacks 

that strike targets in space and 

cyberspace and affect capabilities 

and events in other domains should 

be the basis for assessing their implications and determining whether 

responses in different domains are 

proportionate or escalatory.

◆ Development of a shared framework that integrates actions in 

the emerging strategic domains of 

space and cyberspace with actions 

in traditional domains would give 

decisionmakers a better sense 

of which actions and responses 

are expected and accepted in 

real-world scenarios and which 

responses would be escalatory. 

This would support more coherent 

cross-domain contingency planning within the U.S. Government 

and deterrence threats that potential adversaries perceive as clearer 

and more credible.

December 2011

Cent

e

r fo

r Strat

egic ReS

EARCH
2 SF No. 272 www.ndu.edu/inss

possess diverse strategic capabilities that span air, land, 

sea, space, and cyberspace.

Defining Cross-domain: Platforms 

or Effects?

Cross-domain is an ambiguous term. U.S. doctrine 

identifies land, air, and sea as domains. Recent U.S. national security policy and strategy documents recognize 

space and cyberspace as distinct domains as well.2 Assuming that all five are strategic domains, there are at 

least two different ways an action could cross domains.

Cross-domain could be defined according to the 

platform from which an actor launches an attack and 

the platform on which the target resides. Destroying a 

satellite with a ground-launched antisatellite (ASAT) 

missile is a cross-domain attack, whereas destroying 

one with a co-orbital ASAT (for example, a maneuverable satellite) is not. Striking a surface ship with a 

conventional air-launched cruise missile is a cross-domain attack, whereas an attack on the same target with 

a sea-launched cruise missile (SLCM) is not. Defining cross-domain by platforms demonstrates that crossdomain operations are not new. Air attacks on naval 

forces, naval attacks on air forces, and attacks from both 

domains on ground forces are common in modern warfare. Indeed, in many instances, a cross-domain operation might simply be the most expedient option. As an 

example, a nation under attack by SLCMs might, for a 

variety of reasons, be able to attack the adversary’s naval 

assets more quickly with aircraft than with submarines 

and surface ships.

This definition might be too simplistic. Most U.S. 

military forces on land, in the air, and at sea make use of 

cyber and space assets, and most complex missions integrate 

contributions from multiple domains. One could even argue that a precision conventional strike is a cross-domain 

attack, regardless of whether the attacking platform and 

target are in the same domain, if it utilizes satellites and 

computer networks. By the same reasoning, characterizing 

a cyber attack—as opposed to cyber exploitation—against 

U.S. military computer networks as single-domain is misleading. If successful, such an attack would have important 

cross-domain effects: it would undermine the air, ground, 

or naval forces that depend on the degraded computer networks. These indirect effects in other domains are often the 

primary purpose of cyber attacks.3

 The same logic applies to 

attacks with co-orbital ASATs; even if the platforms are in 

the same domain, the effects are cross-domain.

Thus, cross-domain can also be defined according to 

the effects of an operation. Under this approach, an attack is cross-domain if its intended consequences unfold 

in a different domain than its target. This definition illuminates that inter-domain relationships (our own and our 

adversary’s) create strategic vulnerabilities.4 For example, 

U.S. precision conventional strike operations depend on 

access to multiple domains. A potential adversary might 

be incapable of destroying U.S. aircraft or nuclear-powered cruise missile submarines, but it might be able to attack the space and cyber assets that enable these platforms 

to destroy targets. This appears to be the logic underlying 

China’s interest in counterspace and cyber attacks: such attacks shift the conflict to domains where China’s offensive 

forces have an advantage over U.S. defenses, thereby altering U.S. capabilities in domains (air and sea, for example) 

where China would otherwise be at a disadvantage.5

 This 

cross-domain approach would be ineffective if U.S. air, sea, 

and ground forces did not depend heavily upon space and 

cyber assets. Without this link, China would be unable to 

translate U.S. vulnerability in space and cyberspace into an 

operational impact in other domains. Cross-domain attacks thus enable an actor to best utilize its strengths and 

exploit an adversary’s vulnerabilities in some instances. 

Reports that the United States considered launching a 

cyber attack at the start of North Atlantic Treaty Organization operations in Libya suggest that the U.S. military 

cross-domain attacks enable an 

actor to utilize its strengths and 

exploit an adversary’s vulnerabilities
www.ndu.edu/inss SF No. 272 3 

also perceives cross-domain attacks as useful for exploiting 

adversary vulnerabilities.6

Cross-domain Operations 

and Deterrence

These definitions highlight the fact that military actors frequently cross domains. Indeed, U.S. military posture 

is inherently cross-domain: U.S. offensive and defensive 

weapons are distributed across air-, sea-, and groundbased platforms; space and cyber assets are ubiquitous in 

U.S. military operations and engender advantages in other 

domains; and it is highly unlikely that future U.S. conflicts 

will unfold exclusively within one domain. From this perspective, U.S. deterrence is inherently cross-domain too: 

when the United States threatens to respond to actions 

that endanger U.S. and allied interests, it threatens, albeit 

implicitly in most cases, cross-domain responses. The platforms the United States employs, the targets it attacks, 

and the effect of the attack might be in different domains 

and might differ from the domains utilized in and affected 

by the adversary’s initial attack.

By the same logic, the United States traditionally deters 

attacks in general, without distinguishing between attacks 

that cross domains and those that do not. Naval attacks on 

naval forces are not inherently more or less dangerous than 

air attacks on naval forces. The United States attempts to 

deter both, and the means, target, and scale of the U.S. response to either would depend on the effects of the attack 

and U.S. objectives rather than the domains involved. 

Thus, the United States deters attacks, regardless of 

whether the attacks cross domains, by threatening responses 

that will likely cross domains and differ from the initial attack. Given that cross-domain deterrence is neither new 

nor rare, the real question underlying recent interest in the 

topic is: How can the United States mitigate vulnerabilities 

that stem from its dependence on space and cyberspace? 

Both are offense-dominant domains where U.S. defenses 

are inadequate and policymakers are uncertain about how 

to credibly threaten to impose costs on aggressors and deny 

benefits of attacks. Although potential adversaries depend 

on space and cyberspace less than the United States does, 

this does not explain why threats to respond to counterspace 

and cyber attacks in other domains are considered less credible than cross-domain responses to air, land, or sea attacks.

Shared Framework for Assessing 

Proportionality and Escalation in 

Space and Cyberspace

A concept Thomas Schelling explored in Arms and 

Influence is a useful starting point for answering these 

questions. Schelling argued that deterrence threats are 

more comprehensible to potential adversaries, and thus 

more credible, if they are proportionate with and connected to the actions they are intended to deter: 

There is an idiom in this interaction, a tendency 

to keeps things in the same currency, to respond in 

the same language, to make the punishment fit the 

character of the crime. . . . It helps an opponent in 

understanding one’s motive, and provides him a 

basis for judging what to expect as the consequences 

of his own actions . . . the direct connection between 

action and response helps to eliminate the possibility 

of sheer coincidence and makes one appear the 

consequence of the other.7

Of course, such communication requires that countries interpret military actions and reprisals similarly—in 

other words, that they communicate through a shared 

idiom of action.

Schelling also acknowledged that breaking a pattern of behavior (that is, escalation) might be necessary 

in some circumstances “to catch an adversary off balance, 

to display unreliability and dare the adversary to respond 

in kind.” Even then, however, a shared understanding of 

limits, norms, and expected responses creates a necessary 

countries lack a shared framework 

for interpreting how counterspace 

and cyber attacks fit into an 

escalation ladder
4 SF No. 272 www.ndu.edu/inss

frame of reference by which actors distinguish between 

proportionate and escalatory behavior: “Breaking the 

rules is more dramatic, and communicates more about 

one’s intent, precisely because it can be seen as a refusal 

to abide by rules.”8

The idiom of military action was never as coherent, 

communicable, and universally recognized in reality as 

it is in Schelling’s prose. Nevertheless, during the Cold 

War, there was a generally accepted escalation ladder 

from conventional to chemical and biological to nuclear 

weapons. Within a conventional conflict, there has been 

an understanding that escalation can occur by broadening the geographical area of fighting, expanding the targets attacked (for example, shifting from narrow military 

to broader societal targets), and increasing the intensity 

of violence (for example, using more bombs per sortie or 

shifting to more destructive conventional weapons). The 

salient thresholds differ in every conventional conflict.

Unfortunately, countries lack a shared framework 

for interpreting how counterspace and cyber attacks fit 

into an escalation ladder. Competition and vulnerability in space and cyberspace are new relative to land, air, 

and sea. Countries have less experience fighting wars in 

which space and cyberspace are part of the battlefield. 

Unlike conventional and nuclear weapons, experts are 

less certain about the precise effects of attacks in these 

domains.9

 For these reasons, a widely shared framework 

for judging how counterspace and cyber attacks correspond with interactions in other domains and, more 

broadly, with political relations between potential adversaries during peacetime, in crises, and in wars does not 

yet exist. Without one, decisionmakers will have difficulty distinguishing between proportional and escalatory 

attacks and reprisals that cross from traditional strategic 

domains into these newer ones and vice versa. 

The absence of a shared framework within the U.S. 

strategic community complicates effective cross-domain 

contingency planning. Developing coherent, effective, 

and usable options for responding to attacks in space and 

cyberspace requires that military planners in the different Services and combatant commands possess similar 

assumptions about cross-domain proportionality and 

escalation. For example, Principal Deputy Under Secretary of Defense for Policy James Miller testified that U.S. 

responses to counterspace attacks “could include necessary and proportional responses outside of the space domain.”10 Yet there are a variety of types of counterspace 

attacks and even more potential nonspace targets for U.S. 

reprisals. A common framework would help planners 

determine which “nonspace” responses best correspond 

with counterspace attacks of varying scope and severity.

The absence of a shared framework between the 

United States, allies, and potential adversaries undermines deterrence and increases the potential for 

miscalculation. Effective deterrence requires that U.S. 

officials influence potential adversaries’ perceptions 

of the likely consequences of the actions the United States wishes to deter. The United States might 

threaten to respond to a particular type of attack in 

space or cyberspace by employing different capabilities against different targets in other domains. Such 

threats, however, are less likely to resonate as credible 

with potential adversaries if they do not understand 

U.S. assumptions about how domains are linked and 

why a particular response is a logical and proportional 

reaction to the initial attack.

As an example, imagine the United States threatened to respond to ASAT attacks on U.S. intelligence, 

surveillance, and reconnaissance (ISR) satellites with 

attacks against the adversary’s air defense network. 

The logic underlying this policy is that the United 

States might employ ISR aircraft over the adversary’s 

territory to compensate for the lost satellites. Attacks 

on the air defense network would be necessary to enthe absence of a shared framework 

undermines deterrence and 

increases the potential 

for miscalculation
www.ndu.edu/inss SF No. 272 5 

sure that the aircraft could effectively penetrate the 

country’s airspace. This policy is proportional because 

the United States is restoring its lost ISR capability, thereby denying the benefits of the ASAT attack. 

However, the U.S. response would be different from 

the adversary’s attack. Instead of responding in space, 

the United States would attack targets on or around 

the adversary’s homeland. To further complicate the 

situation, the United States might use conventional 

weapons to destroy the air defense network even if the 

initial ASAT attack was nonkinetic. Without a shared 

framework, potential adversaries might consider this 

deterrence threat illogical and therefore not credible. 

If deterrence failed, they might perceive such a U.S. response as arbitrary and escalatory. Even with a shared 

framework, they may still consider this response as 

escalatory, but they would also understand it to be a 

likely consequence of employing ASATs against the 

United States before authorizing an attack.

To be clear, a shared framework would not and 

could not prescribe set actions for every imaginable 

scenario. Rather, it would define a generic escalation 

ladder, a tacit or loosely defined code of conduct that 

would give decisionmakers a better sense of which actions and responses are expected and accepted in realworld scenarios and which would cross thresholds that 

escalate the situation. This would pave the way for more 

coherent cross-domain contingency planning within 

the U.S. Government and U.S. deterrence threats that 

potential adversaries perceive as clearer and more comprehensible and credible. The United States would also 

have a better understanding of the calculus of potential 

adversaries in their efforts to deter U.S. actions. Cultivating such a shared framework is a constructive goal 

for the future because deterrence, crisis management, 

and escalation control would be easier if different countries interpreted proportionality, connectedness, and 

escalation similarly. Engaging the U.S. strategic community in a thorough dialogue on these issues is the 

first step toward achieving this goal. Forming a deterrence working group of regionalists, functionalists, and 

legal experts might be a fruitful approach to starting 

this conversation.

What would be the basis for assessing counterspace and cyber attacks in a shared framework? Must 

responses to kinetic attacks also be kinetic to be proportional? Is a kinetic response to a nonkinetic attack 

always escalatory? Can a cyber attack be proportional 

to a cruise missile strike? How do officials compare 

attacks that strike targets in some domains and affect 

capabilities and events in other domains? Counterspace and cyber attacks can vary widely in intensity, 

from the equivalent of a tap on the shoulder to a fist 

in the face. Clearly, the mere act of extending the conflict into these domains is an insufficient metric for 

evaluating attacks and calibrating responses. Rather, 

the real-world effects of such attacks, both within the 

domain of the attack and in other domains, should 

determine whether they are escalatory and which responses would be appropriate.

Variables in a Shared Framework

Cultivating a shared framework between potential 

adversaries for assessing effects and formulating appropriate responses is difficult regardless of how many 

domains are involved. U.S. and foreign officials interpret 

events through different prisms. Cultural differences, 

contrasting strategic objectives, differences in force structure and doctrine, and differing strengths and vulnerabilities can cause decisionmakers in the United States 

and other countries to reach different conclusions about 

proportionality and escalation.11 This challenge is not 

new, but the uncertainties in emerging strategic domains 

discussed in the previous paragraphs might exacerbate it.

Imagine that China interferes with U.S. satellites 

via nonkinetic means (laser-dazzling or jamming) during a military crisis that has yet to escalate into an armed 

conflict. The United States might attempt to undermine 

China’s ability to attack U.S. satellites, perhaps by scrambling its space-tracking data through a cyber attack. One 

could argue that this response is proportional because 

it is limited to systems that China is already employing 
6 SF No. 272 www.ndu.edu/inss

against the United States and does not cross the kinetic 

threshold. On the other hand, one could argue that attacking in a new domain is escalatory, opening the door 

to reprisals and counterreprisals in cyberspace and other 

domains. Would Chinese officials distinguish between 

attacks on military computer networks and computer 

networks that support the regime’s domestic security operations? If not, they might interpret this “proportional” 

response as an existential assault, especially if they believe that U.S. cyber attacks will cause collateral damage 

to computer networks other than the one targeted.

What if the initial Chinese ASAT attack is kinetic? 

Would U.S., allied, and Chinese officials perceive a nonkinetic response against China’s space tracking capability 

as weak even if it succeeded in protecting U.S. satellites? 

On the other hand, would kinetic attacks on the ASAT 

weapons China is employing be proportional? Or would 

crossing the geographic threshold (assuming the targets 

are on mainland China) make this response escalatory? 

One could argue that a symmetrical response—a kinetic 

attack on a Chinese satellite—is proportional. However, 

if satellites play a smaller role in Chinese military operations, one could also argue that such a response is less 

than proportionate because it does not impose comparable operational costs on China.12

The balance between offense and defense in these 

domains will also influence perceptions of effects, escalation and proportionality, and optimal deterrence strategies. For example, if offense continues to dominate in 

space and cyberspace and potential adversaries want to 

attack U.S. assets in these domains precisely because 

they are the U.S. military’s “soft underbelly,” U.S. stakes 

in any conflict would grow exponentially after such attacks occur because the effects in other domains would 

be profound. As a result, U.S. officials might feel pressure to take preemptive action prior to such an attack, 

or they might take risks to quickly terminate a conflict 

and punish the adversary in its aftermath. The linkage 

between vulnerabilities in space and cyberspace and the 

effectiveness of U.S. capabilities in other domains that 

makes U.S. satellites and computer networks high-value 

targets also makes the threat of a strong reprisal more 

credible: it would be proportionate to the effects of the 

attack. Conveying this to potential adversaries would be 

a central component of a deterrence strategy. Emphasizing this link might even enhance the credibility of the 

U.S. commitment to retaliate.

Alternatively, the United States might become capable of denying adversaries the benefits of attacks in 

these domains through cyber defenses and substituting 

terrestrial assets for satellites. In this case, U.S. deterrence 

strategy would strive to convince potential adversaries 

that they cannot affect U.S. ground, air, naval, and nuclear forces by attacking satellites and computer networks. 

Such a message might make U.S. threats to respond offensively appear disproportionate and less credible, but 

this would be a worthwhile tradeoff if the United States 

developed a defensive advantage in space and cyberspace.

Decisionmakers will also perceive attacks in space 

and cyberspace differently depending on the context. Attacks on military satellites and computer networks might 

be expected and accepted once a conventional war has 

started. But similar attacks might trigger a conventional conflict if they occur prior to hostilities, when both 

countries want to prevent a crisis from escalating into a 

war but are concerned about being left blind, deaf, and 

dumb by a first strike in space and cyberspace. Proportionality and escalation are relative concepts: actions that 

are escalatory during crises might be proportionate in 

limited wars and underwhelming responses as the scope 

and intensity of a conflict increase.

A related issue is whether U.S. reactions to cyber 

exploitation during peacetime would affect deterrence in 

actions that are escalatory during 

crises might be proportionate in 

limited wars and underwhelming 

responses as the scope and intensity 

of a conflict increase
www.ndu.edu/inss SF No. 272 7 

crises. Though the technology and operations of cyber exploitation and cyber attacks are similar, the goals and effects are different: exploitation extracts information from 

computers and networks without authorization; attacks 

destroy, degrade, or alter them to achieve effects in other 

domains.13 But news outlets frequently describe incidents 

of cyber exploitation against the U.S. Government as cyber 

attacks and evidence of an ongoing war in cyberspace.14

Conflating these operations contributes to the impression 

that U.S. deterrence has already failed. Potential adversaries might conclude that U.S. threats to respond to cyber 

attacks in other domains lack credibility based on how the 

United States reacted to previous exploitation operations. 

This perception might affect how they calculate risks and 

benefits of cyber attacks in crises. How can U.S. officials 

publicly convey that cyber exploitation and attacks pose 

different threats and require different responses, especially 

given the overlap between the two? Emphasizing that the 

real-world effects of attacks and exploitation differ might 

be a first step toward establishing a threshold between 

the two. This message would reinforce that deterrence has 

not failed because the effects of exploitation in cyberspace 

have not yet warranted U.S. military responses in other 

domains. It clarifies the types of actions that the United 

States is attempting to deter.

Some strategists may conclude that proportionate 

counterspace and cyber responses are impossible because 

escalation control in these domains is too difficult. There 

are an “infinite number of scenarios that are neither indicative of a minor harassing incident of jamming nor 

strategic attack” in space and cyberspace.15 Assessing 

the effects of such attacks and choosing appropriate responses amid the stress and confusion of a military crisis 

might be difficult. U.S. and foreign officials likely will 

have differing views about the severity of nonkinetic disruptions that defy easy categorization, and the obstacles 

to developing a common framework might be too formidable. Furthermore, the effects of sophisticated attacks 

on satellites and computer networks might be indiscriminate and too difficult to predict. In this case, a deterrence 

strategy could emphasize that limited counterspace and 

cyber attacks carry an intolerable risk of misperception, 

miscalculation, and unintended escalation. Evoking 

“threats that leave something to chance,” U.S. officials 

could credibly argue that they are uncertain about what 

they would do because such attacks would involve “a process that is not entirely foreseen . . . reactions that are 

not fully predictable . . . decisions that are not wholly 

deliberate . . . events that are not fully under control.”16

Of course, expressing trepidation about unintended escalation could backfire. Adversaries may conclude that 

threatening such attacks would yield U.S. concessions.

Conclusion

Many weapons systems and most military operations 

require access to multiple domains (land, air, sea, space, 

and cyberspace). These linkages create vulnerabilities that 

actors can exploit by launching cross-domain attacks; the 

United States may seek to deter such attacks by threatening cross-domain responses. Yet both the U.S. Government and potential adversaries lack a shared framework 

for analyzing how concepts such as proportionality, escalation, credibility, and deterrence apply when capabilities in 

space and cyberspace not only enable operations in other 

domains but also are part of the battlefield. The real-world 

effects of attacks that strike targets in space and cyberspace and affect capabilities and events in other domains 

should be the basis for assessing their implications and 

determining whether responses in different domains are 

proportionate or escalatory.

Integrating actions in the emerging strategic domains of space and cyberspace with actions in traditional 

domains in a clear escalation ladder would be a first step 

toward more coherent cross-domain contingency planning within the U.S. Government. Communicating this 

framework to potential adversaries would contribute to 

more effective deterrence and crisis management.

Notes 1 Richard Smoke, War: Controlling Escalation (Cambridge: Harvard University Press, 1977), 252.

2 See Department of Defense (DOD), Quadrennial Defense Review Report (Washington, DC: DOD, February 2010), 33–34, 37–39; 
8 SF No. 272 www.ndu.edu/inss

The White House, National Security Strategy (Washington, DC: The 

White House, May 2010), 22; DOD, National Security Space Strategy

(Washington, DC: DOD, January 2011); The White House, International Strategy for Cyberspace: Prosperity, Security, and Openness in a 

Networked World (Washington, DC: The White House, May 2011); 

DOD, Department of Defense Strategy for Operating in Cyberspace

(Washington, DC: DOD, July 2011). 

3 A 2009 National Research Council report defined cyber attacks

as deliberate actions that “alter, disrupt, degrade, or destroy adversary 

computer systems or networks or the information and/or programs 

resident in or transiting these systems or networks,” whereas cyber 

exploitation is extracting information from computer systems or 

networks without authorization. The report demonstrates that the 

intended effects of cyber attacks occur in other domains: “Direct or 

immediate effects are effects on the computer system or network 

attacked. Indirect or follow-on effects are effects on the systems and/

or devices that the attacked computer system or network controls or 

interacts with, or on the people that use or rely on the attacked computer system or network. . . . the indirect effect is often the primary 

purpose of the attack.” National Research Council, Technology, Policy, 

Law, and Ethics Regarding U.S. Acquisition and Use of Cyberattack 

Capabilities (Washington, DC: National Academies Press, 2009), 80. 

4 For more on inter-domain relationships and vulnerability, see 

Mark E. Redden and Michael P. Hughes, Global Commons and Domain Interrelationships: Time for a New Conceptual Framework? INSS 

Strategic Forum 259 (Washington, DC: National Defense University 

Press, October 2010). 

5 For a discussion of the role of space, counterspace, and cyber 

capabilities in China’s military strategy, see David C. Gompert and 

Phillip C. Saunders, The Paradox of Power: Sino-American Strategic Restraint in an Age of Vulnerability (Washington, DC: National Defense 

University Press, 2011), chapter 3; James Dobbins, David C. Gompert, David A. Shlapak, and Andrew Scobell, Conflict with China: 

Prospects, Consequences, and Strategies for Deterrence (Santa Monica, 

CA: RAND, 2011), 5–7; Office of the Secretary of Defense, Annual 

Report to Congress, Military and Security Developments Involving the 

People’s Republic of China 2010 (Washington, DC: DOD, August 

2010), 22–37; Jan Van Tol with Mark Gunzinger, Andrew Krepinevich, and Jim Thomas, AIRSEA Battle: A Point-of-Departure Operational Concept (Washington, DC: Center for Strategic and Budgetary 

Assessments, 2010), 17–47; Roger Cliff et al., Entering the Dragon’s 

Lair: Chinese Anti-Access Strategies and their Implications for the United 

States (Santa Monica, CA: RAND, 2007), 51–60.

6 For reports of U.S. debates about launching a cyber attack 

against Libya, see Eric Schmitt and Thomas Shanker, “U.S. Debated 

Cyberwarfare in Attack Plan on Libya,” The New York Times, October 

18, 2011, and Ellen Nakashima, “Pentagon Officials Had Weighed 

Cyberattack on Gaddafi’s Air Defenses,” The Washington Post, October 

18, 2011. 

7 Thomas C. Schelling, Arms and Influence (New Haven: Yale 

University Press, 1966), 146–149.

8 Ibid., 150–151.

9 For a discussion of expert uncertainty surrounding intended 

and cascading effects of cyber attacks, see National Research Council, 

121–128. 

10 James N. Miller, testimony for the House Armed Services 

Committee, Subcommittee on Strategic Forces, March 2, 2011. 

11 For a theoretical/historical study of the causes and implications of doctrinal differences in U.S.-China relations, see Christopher 

P. Twomey, The Military Lens: Doctrinal Differences and Deterrence 

Failure in Sino-American Relations (Ithaca: Cornell University Press, 

2010). 

12 This example demonstrates that symmetrical and asymmetrical responses to attacks in space and cyberspace are not synonymous with proportionate and escalatory responses; however, since 

symmetrical responses attack the same type of target with the same 

type of weapon in the same domain as the initial attack, it likely 

would be easier for different countries to reach similar assessments 

about whether such responses are proportionate or escalatory. Assessing asymmetric responses against targets in the same domain as 

the initial attack—which might attack the same type of target with 

different types of weapons, different types of targets with the same 

type of weapon, or different types of targets with different types of 

weapons—might be more difficult. Assessing asymmetric responses 

against targets in different domains than the attack would likely be 

the most difficult because it requires a shared standard for determining equivalencies across domains. 

13 National Research Council, 149–152.

14 For example, Michael Riley and Ashlee Vance, “Cyber Weapons: The New Arms Race,” Bloomberg Businessweek, July 20, 2011.

15 Susan J. Helms, “Schriever Wargame 2010: Thoughts on Deterrence in the Non-Kinetic Domain,” Air Force Space Command High 

Frontier 7, no. 1 (November 2010), 14. 

16 Schelling, 95.

The Center for Strategic Research within the Institute for 

National Strategic Studies provides advice to the Secretary of Defense, Chairman of the Joint Chiefs of Staff, and 

unified combatant commands through studies, reports, 

briefings, and memoranda. The center conducts directed 

research and analysis in the areas of strategic and regional studies and engages in independent and leading-edge 

research and analysis in related areas.

The Strategic Forum series presents original research 

by members of NDU as well as other scholars and 

specialists in national security affairs from the United 

States and abroad. The opinions, conclusions, and recommendations expressed or implied within are those of the 

contributors and do not necessarily reflect the views of the 

Defense Department or any other agency of the Federal 

Government. Visit NDU Press online at www.ndu.edu/press.

Nicholas Rostow

Director

Center for Strategic Research

Phillip C. Saunders 

Director of Studies

Center for Strategic Research

Institute for National Strategic Studies

Hans Binnendijk

Director

INSS

Acknowledgments

This Strategic Forum benefited greatly from discussions with 

and comments by Elaine Bunn and Phillip Saunders, from comments by peer reviewers CAPT Mark Redden and Col Michael 

Hughes, and feedback from a presentation for the Office of the 

Secretary of Defense for Policy.