*I recently wrote this policy memo for the Global Intelligence Trust and decided to post it here as well.
With rapid advancements in private space development and the maturation of space-based technologies, major powers are beginning to pivot toward space as the next military domain. Currently, space-based military capabilities are almost exclusively intelligence-oriented. Countries utilize spy satellites and GPS systems to enhance the effectiveness of their forces, but they do not employ kinetic, offensive weapons above the Earth’s mesosphere, the middle layer of the atmosphere. However, the rapid expansion of ground-based anti-satellite (ASAT) weapons systems poses a threat to the continued peaceful development of space. Developing a coherent and coordinated U.S. space policy is, therefore, strategically vital. The U.S. must strike a delicate balance, working to ensure the peaceful development of space while also guaranteeing that rival powers do not threaten vital American interests. This report seeks to examine three major questions. First, what current legal regimes govern and regulate the use of military activity in space? Second, how is weaponization occurring in the status quo? Third, what strategy should the United States pursue in the near to medium term?
Currently, the United Nations regulates certain activities in space. The United Nations Outer Space Treaty in particular seeks to limit conflict in space by banning the deployment of nuclear weapons in space, ensuring that celestial bodies are utilized only for peaceful purposes and guaranteeing that space is free to be exploited and developed by all of humanity. However, these provisions still permit the weaponization of space through the use of orbital, non-nuclear weaponry and ASATs. Recent attempts at bolstering international regulations against space weaponization, like the Space Preservation Treaty, have been vetoed by the United States. This is not surprising, as it is rare for great powers to voluntarily constrain themselves in areas in which they possess a comparative advantage. Moreover, the United States faces credible commitment problems: It would be easy for rival spacefaring states like China or Russia to exploit loopholes or vague terminology to generate strategic advantages. Indeed, Russian and Chinese hesitance to sign on to the E.U. Space Code of Conduct suggests that their motives are not necessarily benign and might actively imperil U.S. interests. In short, while there is meaningful multilateral commitment to peaceful space development, along with significant international regulations governing the exploitation of space, mutual distrust between the major space powers suggests that further development of treaties designed to ensure the peaceful development of space is unlikely. With the U.S. as the dominant world power, and the ever-present threat of other states reneging on their commitments, there is simply not much incentive for the U.S. to support or ratify treaties that further constrain its military presence in space. However, if the United States wants to create progress toward a more stable and secure space domain, it needs to be willing to concede on certain areas of space weaponization. The challenge, then, is to create a treaty that is not so limiting as to be unpalatable to major actors like the U.S., Russia, and China, yet still has enough power to meaningfully constrain the rapid proliferation of space weapons systems.
Before proceeding, it is important to clarify the distinction between space militarization and space weaponization. Militarization simply describes the use of space for military purposes. For instance, the deployment of spy satellites or military GPS systems would constitute space militarization. Space weaponization is distinct, however, in that it describes the deployment of explicitly offensive weapons systems designed for use in space. Ultimately, space weaponization is far more concerning than space militarization because it would potentially engender militarized disputes in space, imperiling the vast array of satellites necessary to maintain the modern, globalized world. Fortunately, it is not too late to limit space weaponization. Significant work must be done, however, if the United States is to limit the proliferation of space weapons systems.
ASATs represent the gravest threat to peaceful space development. As Michael Krepon and Christopher Clary note, “Today, the threat environment to satellites is both broader and shallower. It is broader because the technology necessary for attacking satellites is more accessible. It is shallower, however, because the United States does not face a peer competitor with the resources and the ambitions of the Soviet Union.” In other words, the threat vectors are more diverse and unpredictable, but the risk of any particular vector is diminished because the U.S. does not face any peer competitors. The situation is even more muddled by the fact that the U.S. military is far more reliant on space than other militaries. In short, while a space war that disrupts global communication would be deleterious to all countries, it would be particularly damaging to the United States due to the heavy U.S. reliance on space-based assets designed to support terrestrial military operations. However, the vast space infrastructure of the United States is also an advantage in that it grants U.S. influence over other actors like private space contractors. As Krepon and Clary point out, “The United States can influence commercial providers to deny these services during a conflict. Means of suasion could include legal measures, financial inducements, and diplomatic pressure.” In short, the current situation regarding space is highly complex. The United States enjoys substantial advantages insofar as its space capabilities and military satellite technology are unmatched. Moreover, its weight in the international market grants it leverage over companies that might otherwise assist American adversaries. However, the U.S.’ heavy reliance on space for both economic and military purposes makes the United States comparatively more vulnerable to a conflict above the Earth’s mesosphere.
There are three primary ways that satellites can be neutralized. First is the use of nuclear weapons. The detonation of nuclear weapons in space would generate an electromagnetic pulse (EMP) that could fry satellite electronics, rendering them inoperable. Furthermore, if nuclear weapons were to be detonated in low earth orbit (LEO), the Earth’s magnetic field would trap electrons, potentially destroying the majority of LEO satellites within a matter of weeks. Nuclear usage seems unlikely, though, for a number of reasons. First, as explained previously, nuclear usage would be in violation of the Outer Space Treaty. Second, as Nina Tannenwald has documented, there exists a strong taboo against the use of nuclear weapons. Third, the use of nuclear weapons in space might lead to further nuclear escalation, turning a limited anti-satellite strike into a regional or even global nuclear war. States are, therefore, unlikely to utilize nuclear weapons to conduct anti-satellite operations.
Instead of employing nuclear weapons, states can utilize kinetic kill interceptors to destroy satellites. Indeed, China recently demonstrated this capability when it shot down one of its own satellites during an ASAT test in 2007. Kinetic kill systems are advantageous because they avoid many of the problems associated with nuclear detonations. They are less likely to lead to nuclear escalation, and they are more discriminating in their targeting because they don’t release damaging electrons and EMP pulses. However, kinetic kill ASATs do generate large amounts of debris that can remain in orbit for an extended period of time, potentially damaging other satellites. Thus, kinetic kill systems still include significant costs, making their use unlikely except in the case of a large scale war. The third major avenue through which states and non-state actors can interfere with satellite systems is electronic jamming and spoofing. Hacking satellites is surprisingly simple. In fact, in 1999, a group of British hackers was able to seize control of a military communications satellite. Clearly, then, electronic attacks represent a powerful asymmetric capability that can be utilized for targeted attacks and a tactic that non-space powers can use to exert influence in Earth’s orbit. Because of the relatively low barriers to entry, electronic attacks will likely be utilized heavily by non-state actors like terrorists, as well as states that lack the ability to develop nuclear or kinetic kill ASAT technologies. While there likely are methods by which military satellites can resist electronic jamming and spoofing, most commercial satellites are simply radio repeaters and are particularly vulnerable to hacking. Thus, even if crucial military satellites are hardened against attack, rogue groups could still easily target commercial satellites, disrupting global communications and, by extension, the global economy.
Regardless of which method of attack is utilized, any attack on the global satellite network would likely escalate, making space war particularly dangerous. Two dynamics, in particular, make an attack on space assets escalatory. First, the importance of communications and GPS satellites for the functioning of the global economy means that states have an incentive to strongly resist attacks on the satellite network. In other words, major powers like the United States would have an incentive to rapidly escalate in order to deter future attacks. By utilizing a strategy of deterrence by punishment, states could signal that transgressions against the norms of peaceful space development will trigger severe consequences. In order to make this deterrent measure credible, however, states would have to deploy significant military force in order to send a costly signal. The second and more worrisome escalation dynamic is the close linkage between military satellites and nuclear forces. As Krepon explains, “Satellites are connected in many ways to the execution of nuclear war-fighting plans by helping with weather forecasting; targeting, indications and warning of attacks; assessing damage and maintaining command, control and communications.”
In short, an attack on early warning or targeting satellites might cause states to believe they face an impending nuclear attack. With command and control satellites being eliminated, states could face a “use it or lose it” dynamic in which they are forced to either launch their nukes immediately or face the potential of not being able to launch their nukes at all. Even states like the U.S. that have redundant systems and secure second strike capabilities might miscalculate. The rapid elimination of nuclear command and control capabilities would lead to chaos and potentially an accidental nuclear launch. Clearly, the potential dangers of a conflict in space are grave indeed.
What, then, should the United States do to preserve its military dominance while still ensuring the peaceful development of space? Broadly, the United States should pursue three major objectives. First, it should work to create a treaty in line with Ross Liemer and Christopher Chyba’s recommendations. Namely, the United States should commit to a ban on the testing of debris-generating weapons systems, coordinate with other nations to combat space debris, and work to develop confidence-building measures between the major space powers. Second, the United States should work to maintain ASAT parity with rivals. Ensuring that the U.S. has the capabilities to retaliate against attacks is crucial to maintaining deterrence. However, the United States should not aggressively invest in ASAT capabilities in a strategy designed to overwhelm rivals. This would risk a dangerous ASAT arms race, raising tensions and increasing the odds of inadvertent escalation. Third, the United States should declare a clear policy of massive retaliation should another country launch an attack on U.S. or allied space assets. Only a clear and unambiguous message will ensure that potential adversaries understand the seriousness with which the U.S. views the security of the space domain. As a part of this massive retaliation, the United States should clarify that responses to attacks directed at space assets would not necessarily preclude nuclear use. While this policy potentially increases the risk of nuclear retaliation, compartmentalization of space as separate from other domains (including nuclear) weakens deterrence and invites aggression.
In conclusion, space is a vital domain for both U.S. national security as well as for the smooth functioning of the global economy. Unfortunately, despite space being an integral component of the “global commons,” rules governing military conduct in space are, at best, incomplete. The rapid advancement in space-related technology and the development of potent ASAT weaponry represents a potentially dangerous and destabilizing dynamic that might upset the peace and stability that has permitted the sustained development of space up to this point. The U.S. faces tough choices ahead, and it must work to create a set of rules and norms to govern space conduct. By combining a strong institutional regime with a credible deterrent capability, the United States can help shape the space domain into a peaceful and beneficial space for all countries.
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