From the Archives | Deterrence Scenarios in Outer Space

By Kaili Ayers

The expansion of space-based capabilities has ballooned over the past  six decades in response to the rapid growth of technological  advancements and the simultaneous lowering of their production costs. Satellites are now relied upon to provide support for essential military  operations in addition to global society’s daily activities. However, the largely inferential nature of satellite capabilities suggests that deterrence as  a theoretical and strategic construct may not effectively function in the outer  space environment. Juxtaposed against nuclear deterrence, which relies on the physical  exhibition of military power, satellite capabilities such as non-kinetic physical, electronic, and cyber are not readily visible, thus diminishing the  levels of perceptibility and signaling strength necessary for successful  deterrence.

Thus deterrence, which traditionally has been associated with  the nuclear context, is becoming increasingly unable to address emerging  technologies that sit beyond the scope of conventional weapons capabilities. A proposed category of capabilities termed “inferential” anti satellite (ASAT),[1] are altering the cost-benefit calculus of deterrence based  on their generally non-attributable nature, causing issues to arise with  perceptions of deterrence credibility and signaling. Yet, due to several  factors—including the US moratorium on testing destructive ASAT,  concerns of environmental sustainability, and increased use of grey-zone  and salami tactics by adversaries—inferential and non-kinetic ASATs will  likely be the primary means where conflict in outer space is waged in the  immediate future, thus emphasizing potential negative impacts upon  strategic level deterrence within nuclear and space power arenas.

“Inferential” Anti-Satellite Capabilities 

The four types of counterspace capabilities are 1) kinetic physical,  2) non-kinetic physical, 3) electronic, and 4) cyber. [2] The first type houses  conventional weapons capabilities that represent the pinnacle of traditional  arms: direct-ascent ASAT, co-orbital ASAT, and ground station attacks,  among others. These types of attacks inflict permanent damage to space  systems while simultaneously demonstrating the strength of a state’s  military capabilities. While kinetic physical attacks have the highest  probability of the loss of human life, no state has ever conducted a kinetic  physical attack against another state’s satellite. However, states such as the  United States, Russia, China, and India all have successfully tested direct ascent ASAT weapons.[3]

Non-kinetic physical, on the other hand, can be labeled as the inverse  of the first as it groups together capabilities that are not visibly physical,  including high power radio frequency, high energy-powered lasers (also  referred to as dazzling), neutral particle beams, electromagnetic pulse (EMPs), and high-powered microwave HPM. [4] Such capabilities are able to  exact physical effects on satellites or related infrastructure without making  physical contact. High-powered microwaves for example, can cause  irreversible damage to a satellite’s circuitry, as well as disrupt critical  electronic hardware. These two categories respectively (kinetic and non kinetic), are what Michael Krepon characterizes as demonstrable and  inferred capabilities—so named for their inherent physical or non-physical  attributes. [5]

Electronic capabilities are the means by which space systems  transmit and receive data. They typically refer to uplink and downlink  jamming or spoofing, and target technologies that utilize the electromagnetic spectrum. Like non-kinetic capabilities, electronic counterspace weapons are similarly difficult to attribute; which is due in part  to the difficulty in distinguishing such attacks from accidental interference.  

Lastly, cyber capabilities refer to data intercept or monitoring, data  corruption and seizure of control of a spatial system. Cyberattacks target the  data itself as well as the systems related to the flow of data. They could result  in the loss and degradation of data or services which a satellite provides.  Since the barrier to entry is relatively low; cyberattacks can be contracted  out if an adversary lacks domestic internal cyber capabilities. [6] Overall, in contrast to kinetic physical ASATs which are highly  attributable, cause permanent damage, and simultaneously signal both  capability and the political will of the aggressor state, inferential ASATs are  a broad categorization comprised of capabilities that do not create debris  fields of their targets, and are significantly less visible to third-party  observers. Note that this grouping, which encompasses directed energy,  electromagnetic, radiofrequency, and cyber capabilities, does not strictly  align with the traditional categorizations of counterspace threats. It also can include non-kinetic physical attacks.

For example, military-use EMPs are  categorized as non-kinetic physical attacks, but may be categorized as  “inferential” because they are rapid, invisible, and can affect damage with  indirect contact with a satellite. The distinction of this proposed  categorization is valuable because of the shared inferential traits that pose  challenges to attribution and increased use as a grey zone tactic in the outer  space domain. Thus, in light of this proposed categorization, changing  technological environment, and increased use of grey-zone tactics in the  space domain, we must take a hard look at the underlying theories guiding  national security strategies such as strategic-level deterrence; specifically,  its tenants of credibility and signaling, which could be negatively impacted  by the inferential attributes of new weapons systems.  

Deterrence Credibility and Signaling  

The successful application of deterrence theory in practice is  contingent upon the 1) credible psychological impact upon the adversary, 2)  signaling of an attributable weapons capability, wherein the signal receiver  is able to visibly detect or identify the negative consequences of attack, and  3) the political will to carry out such an attack if attacked by an aggressor.  The proliferation of inferential ASAT capabilities significantly alters this  cost-benefit calculus due to the difficulty of attributing their use in attacks.  Moreover, since conventional weapons capabilities have evolved to include  virtually undetectable forms of attack with little progress towards  attribution, it is reasonable to conclude that the successful operationalization  of deterrence against inferential ASATS will be difficult to achieve in outer  space.  

In deterrence theory, credibility refers to the effective  communication (signal) to an adversary through deterrence posture, so as to  compel the adversary to believe the utility of the planned attack. Since the  value of signaling lies in the opponent’s perception, and because inferential  capabilities engender difficulties in attribution, adversaries will remain undeterred so long as the attack does not register as a threat. [7] Degradation  of credibility occurs when signals are misinterpreted or misperceived, as  well as if there are differing belief systems and intentional interference by  the adversary. [8] If present, these factors are likely to result in a weakened  deterrence posture; this remains especially true when such signals are below  the escalatory threshold of retaliatory response, as is the case with grey-zone  and salami tactics that employ inferential capabilities. Moreover, the small  incremental degradation of satellite infrastructure through strategies that  aim to incapacitate—such as bumping a satellite out of orbit in the hopes of  forcing an operator to burn through its fuel source through repeated  maneuvers, can be a favored strategy with actors who maintain an inferior  position within an asymmetric relationship. [9] 

While falling short of what can be considered an outright hostile move, salami tactics in outer space can be debilitating from an operational  perspective. Salami tactics refer to the “deliberate erosion of a defender’s  redline by consciously attempting to stay below the perceived threshold for  reaction.” [10] Such tactics are strategies that do not quite invoke the  commitment to launch a retaliatory measure, thus creating a situation where  a deterrence posture is weakened because the credibility of the strategy is  similarly degraded. A relatively proportionate response by the actor who  maintains a superior position could be to bolster its defenses by increasing  space situational awareness (SSA) or space domain awareness (SDA),  imposing effective space traffic management (STM), hardening satellite  infrastructure against radiation, and disaggregating capabilities. [11] The lower  barrier to entry, combined with the proliferation of actors and capabilities in  the outer space domain indicate that the use of salami tactics will also rise  in kind. Thus, the current outer space environment is one wherein  spacefaring actors must navigate the complexities of the increasing use of  inferential ASAT and a changing deterrence regime.  

Deterrence Scenario: Hijacked Satellite

To illustrate the potential ramifications of salami tactics in outer  space, coupled with the implementation of inferential ASAT capabilities in  the deterrence context, this article examines a hypothetical scenario where  a US military satellite is compromised by an allegedly rouge Chinese  communications satellite. The scenario begins with the increased presence  of Chinese satellite capabilities within the Asia-Pacific region as part of the  Beidou constellation, which is being used as a tool for the Digital Silk Road  and Belt and Road Initiatives.[12] Chinese satellites are now being used by  states developing their own space programs for their low cost, shorter  acquisition time, technology transfer, as well as coverage of under the established Beidou constellation; which although it is comprised mostly of  positioning, navigation, and timing (PNT) satellites, also includes satellites  dedicated to communication services.[13] In the last six months, China has significantly increased the number  of Beidou-3 satellites in orbit with the hopes of responding to competition  from SpaceX’s Starlink network. However, there is now one Indonesian owned communications satellite manufactured by China that is experiencing  uncontrolled commanding events. While the satellites’ communication  functions are operational, it causes interference with nearby satellites.  

Despite efforts to regain control, the communications satellite is drifting  around the GEO belt towards the direction of a US military missile warning  satellite. It will likely hit, if not cause significant interference to the US satellite corresponding to the time when China plans to conduct a planned  military exercise involving the launch of missiles and other military  systems. As tensions escalate, the situation takes a turn when an  unattributable cyber-attack is launched against US ground control systems  responsible for overseeing a major US-based satellite network responsible  for majority of the US’s radio frequency signal location data. Through a  series of malware injections and network intrusions, the attackers gain  unauthorized access to critical command and control functions, effectively  seizing control of a subset of US commercial satellites and decreasing the  operation of the US’s space situational awareness capabilities.  

Questions to consider for this scenario include: does the trajectory  and subsequent interference of the two Chinese communications satellites by themselves constitute an act of aggression, use of force, or an armed  attack? What types of retaliatory, escalatory, or defensive actions could the  United States take? And, what additional capabilities would be useful in  mitigating the situation?  In this scenario, Chinese salami tactics manifest in the increased  presence of Chinese inferential satellite capabilities within the Asia-Pacific  region, as evidenced by the Digital Silk Road and Belt and Road initiatives  and growing Beidou constellation. This build-up of Chinese technological  capability, despite being operated by Indonesia, contributes to the growing  concern of the US and its allies in the region of China’s expanding influence.  Considering this scenario through a deterrence lens, the first question is  whether a credible psychological impact was created upon US decision  makers. Taking into account the ongoing geopolitical behavior of China in  the South China Sea, its rapid development and testing of rendezvous and  proximity operations (RPO), and its 2007 kinetic ASAT test, all contribute  to the United States’ perceived credibility of China taking incremental  actions to position itself in an advantageous posture within its region and in  outer space. Thus, there is little doubt as to whether a credible psychological  impact was created upon US decision makers. 

The next question is whether China successfully communicated an  attributable weapons capability. In other words, did China clearly signal its  technological capability and did the United States perceive it? At the outset,  it is unclear whether China intended to send a clear signal because of its  reliance on salami tactics, which inherently does not lend itself to clear, non incremental signaling. The facts of the scenario suggest that there is a high  probability that China also launched the cyber-attack on US commercial  satellite infrastructure despite it being unattributed because the attack  aligned with the timing of China’s planned military exercise. Thus, the  question may be alternatively framed as whether the incremental salami  tactics of China in this scenario, combined with its past geopolitical behavior  are sufficient for the United States to perceive an escalatory action.  

The last question this article considers is whether the United States maintains the political will to carry out a retaliatory action. This question  may also be framed as what level of retaliatory measures should the United  States carry out and would those actions be perceived as escalatory or de escalatory in nature. From the US’s perspective, the uncertainty of who carried out the cyber-attack presents a dilemma: if China did in fact conduct  the attack, not taking retaliatory action would not only compromise US commercial infrastructure in outer space, but would also indicate the US’s acquiescence, thus increasing the threshold for retaliatory action. However,  if China did not conduct the attack and the United States retaliated with an  action that led to escalation, the conflict would continue to escalate, leading  to a potentially unfavorable outcome for both sides.

Thus, we are left with  questions of how the United States may respond to supposed Chinese  escalatory actions such that the retaliatory threshold is not breached. Perhaps the most apparent capability the United States should  employ in the first instance of discovering a rouge satellite would be space  domain awareness. If more information about the rouge satellite existed, the  uncertainty about Chinese escalatory actions would be mitigated. For  example, if an inspector satellite could maneuver to take a closer look at the  rouge satellite, it could then identify the rouge satellite’s condition and take  possible mitigating actions, such as using an on-orbit servicing satellite to  alter its trajectory. However, since an unattributed cyber-attack also  occurred that obstructed the operation of a major US commercial satellite  network, it is possible that SDA capabilities would be compromised, resulting in strategic hand-tying the United States in terms of potential  mitigating actions it could take.  

Another point worth noting is that if the cyber-attack was on the  US’s military satellite infrastructure instead of its commercial counterpart,  the deterrence calculus would change, and escalation would be difficult to  avoid. The implications of an attack on military infrastructure in this  scenario would justify US retaliatory escalation, perhaps in the form of  jamming, spoofing, targeting ground-based satellite infrastructure, or  causing interference with satellite sensors to degrade China’s ability to  collect intelligence or reconnaissance data during the period in which China  conducts its planned military exercise. An alternative route of action for the  United States to consider would be taking advantage of diplomatic channels  and pre-established norms of behavior to facilitate communication with  China through international institutions such as the United Nations. While  this option may come at the cost of time, it would be a valuable option to  avoid costly escalation.  Lastly, a potential general solution to the credibility and signaling  problem in the space domain would be to bolster deterrence strategies with  an integrative triad that combines special operations, cyber, and space force capabilities.[14]

While still largely in development, the triad could leverage  space-based competencies, such as space domain awareness, space  forensics, dual-use spacecraft, proximity operations, or on-orbit servicing— to fill the gap left open by weakened attribution capacity, and to deter actions  below the threshold of conflict without having to resort to kinetic-type  ASAT. The question then is whether such space-based capabilities,  especially dual-use spacecraft, will serve to deter or escalate conflict. In  2022, China’s Shijan-21 docked with a defunct Chinese satellite and towed  it into a graveyard orbit. This not only demonstrated China’s technological  advancement, but its ability to conduct counter-space operations under the  pretense of debris removal operations. Such developments point to the trend  of increased reliance on inferential capabilities by adversaries, and negative  implications of strategic level deterrence in outer space.  

Conclusion 

The proliferation of inferential ASAT capabilities presents new  challenges to the space governance regime by introducing uncertainty into  the deterrence calculus through methods such as salami tactics and grey zone warfare. As this scenario demonstrates, deterrence strategies within the  context of such tactics are difficult to achieve as signals may be easily  misconstrued. However, the incorporation of a robust SDA system, as well  as the potential to employ diplomatic channels, will likely serve as crucial  supports to the deterrence calculus. Moreover, while a deterrence triad can  bolster credibility and signaling, inferential ASAT remains below the  threshold for escalation, degrading the integrity and security of outer space  systems over time. Thus, the salience for deterrence within this context is  not only meaningful for its theoretical applications, but because its  successful implementation implies that deterrence as a theory is highly  adaptable, and resilient, and will continue to remain relevant in formulation  of the United States’ national space strategies going forward.