Space and the Right to Self Defense

Executive Summary

Short of directly challenging military pre-eminence, some adversaries’ ability to hold at risk the homeland and key systems constrain our options in response to aggression. The current threat trends promise that this challenge will only increase, further constraining the options of U.S. leaders. This includes options that we have grown to take for granted. Choices to act in space, aerospace, surface, and sub-surface will be deterred by our inability to meet contemporary and future threats. Limiting U.S. leaders’ options, particularly strategic options, could be especially devastating in a crisis.

In particular, several adversaries have prioritized the development of missile forces to hold at risk the U.S. homeland, allies, deployed forces, and space assets.

The threat posed by direct-ascent anti-satellite missiles is especially grave. By holding at risk U.S. space systems, adversaries threaten that which gives the United States much of its military superiority. As aptly stated by the National Security Space Strategy, when combined with other capabilities, space systems allow joint forces to see the battlefield with clarity, navigate with accuracy, strike with precision, communicate with certainty, and operate with assurance. For many years such space systems were both beyond the capability and reach of any potential U.S. adversary. In recent years, recognizing the asymmetric nature of U.S. space dominance together with space assets’ fragility and vulnerability to attack, our adversaries have taken advantage of this U.S. Achilles’ heel by developing weapons to target space assets. While it is true adversaries are developing various types of methods to disrupt or destroy space assets, including co-orbital anti-satellite weapons (ASATs), the scope of this study is limited to the threat to space systems posed by direct-ascent anti-satellite missiles, as these systems are the first to have been demonstrated in actual flight tests.

China has demonstrated an operational direct-ascent anti-satellite missile capability, and has proven that it can reach from low earth orbit to geosynchronous altitudes putting nearly the full spectrum of our defense and intelligence satellites at risk. Not only does this give China a powerful coercive ability, it also creates the temptation to eliminate in a pre-emptive strike the warfighting assets upon which the United States is most reliant. Although China is the most advanced in this regard, other spacefaring adversaries are increasingly able to hold U.S. space assets at risk. Russia has a formative space weapons program and media reports indicate it has tested a direct-ascent anti-satellite missile. North Korea and Iran have each launched satellites into orbit. These developments clearly show the sanctuary status once assumed for U.S. space assets has been irredeemably lost, and, whether we wish it or not, powerfully demonstrates that the space domain is a battlefield.

Our current space defense posture is primarily passive and reactive, an anachronism of the Cold War era during which we had a single superpower adversary and the uneasy deterrence construct relying on Mutual Assured Destruction. Acknowledging its vulnerability in space, the United States has begun to build resiliency into its space architectures, and military leaders are advocating to Congress for the funds necessary to improve space situational awareness (SSA). Both resiliency and a robust SSA capability are critical to a successful U.S. national security space strategy, but are not by themselves enough. The United States cannot prevail in space merely by passively defending itself against hostile force; it must have active defenses as well.

Although there is a place for deeply classified programs and activity toward this end, any credible deterrence strategy is dependent upon the United States making clear to our adversaries the high value the United States assigns to its space assets and that we possess the capability and willingness to defend those assets. Implementing a credible modern deterrence strategy that removes ambiguity concerning the consequences of an attack on U.S. space assets, while fully integrating our space layer to respond to threats across all domains, is the best course for ensuring a secure space environment. To be sure, it is a necessary condition for ensuring and safeguarding future U.S. military pre-eminence.

A critical component of a strengthened and modernized strategic posture that better integrates the space domain is a robust, layered, missile defense system that provides protection of the United States and that which it values most. The current U.S. ballistic missile defense system (BMDS) is composed of land- and sea-based interceptors, cued by sensors on land, at sea, and in space. There is no interceptor layer located in space. While each present-day element of the BMDS plays a significant role in the defense of the U.S. homeland, allies, and deployed forces, the system is designed to handle only limited threats posed by rogue nations. It is not designed to handle the more complex missile threats from near-peer adversaries such as Russia and China. Additionally, the pace at which rogue nations such as North Korea and Iran are improving both the quality and quantity of their own missiles, poses significant challenges for the present system.

This study recommends augmenting the U.S. strategic posture by enabling the use of space for the defense of the United States across military domains; specifically, the United States should immediately begin the necessary steps to deploy a space-based interceptor (SBI) capability.

An SBI capability would dramatically augment U.S. terrestrially- and sea-based defensive capabilities, reduce the demands upon current systems, and provide the United States with the optimal vantage point for destroying enemy missiles regardless of their launch or target location, whether on land, at sea, in the air, or in space. A critical benefit of an SBI layer is the ability to destroy many missiles during their boost phase, while the missile is still over enemy territory and before the enemy can deploy their nuclear warheads, countermeasures, and decoys.

Opponents of SBI offer numerous arguments against deploying the capability, but those arguments are predicated on false assumptions. For example, opponents have argued that deploying SBI would instigate an arms race with countries like Russia and China. But American military strength has not provoked adversaries’ investments in military capabilities; rather, U.S. capability gaps have prompted our adversaries to invest in weapons to exploit U.S. vulnerabilities. The task at hand is to close those gaps in order to deter adversaries’ continued investments. Opponents have also insisted that a kinetic interceptor capability in space remains technically out of reach and is cost prohibitive. However, available technology makes it entirely feasible and affordable in the near term. Others have said that deploying SBI is prohibited by an international treaty and threatens to create devastating permanent space debris, but there is no treaty that prohibits SBI, and the risks from debris are manageable. For example, an enemy missile destroyed in boost phase cannot produce long-lived orbital debris.

We have long since passed the threshold of concern that space will one day become the next battlefield, and we are at a pivotal moment. The United States of America will not maintain its pre-eminent global power status by default nor absent further action. We must choose this path, and if chosen, we must better utilize the space domain to nullify any adversary’s ability to coerce and blackmail the United States with missiles, possibly armed with nuclear weapons. Although missile defense is only one component of the U.S. strategic posture, by optimally defending what the United States values—the entire U.S. homeland, allies, deployed forces, and assets located in space—the BMDS, with SBI, would serve as a powerful deterrent and a critical means of defense should deterrence fail.

The following includes the study’s findings:

•  U.S. adversaries are investing in missile technologies to contest U.S. military pre-eminence and challenge U.S. technical superiority.

•  Adversaries’ ability to hold at risk the homeland and key systems, such as space based systems, will constrain in unacceptable ways our decision-making ability and options in the future.

•  U.S. vulnerabilities to missile attack have not deterred adversaries from investing in the development of offensive weapons, but have instead prompted adversaries to exploit those vulnerabilities.

•  Due to the vulnerability of, and the U.S. reliance on, space assets, adversaries have sought to target those assets with a variety of weapons including direct-ascent anti-satellite missiles.

•  The current layered U.S. ballistic missile defense system (BMDS) is a critical component of the U.S. strategic posture, but its various components are obsolescing and require significant increases in investments. The BMDS must be qualitatively improved in order to outpace the missile threat and close current vulnerabilities.

•  A space-based interceptor (SBI) capability is essential to augment U.S. terrestrially and sea-based capabilities, and keep pace with the threats we face.

•  An SBI capability would enable the United States to better defend against the missile threats to the U.S. homeland, allies, deployed forces, and critical space assets.

•  No treaty or international conventions or norms prohibits the deployment of an SBI capability.

•  Modern technologies can be leveraged to develop an effective SBI capability in the near term and at a reasonable cost.

•  The risk of debris posed by an SBI capability is manageable, and in most cases negligible.

To meet the contemporary and future missile threats that challenge American military superiority and seek to coerce the United States, this study makes the following recommendations:

•  Reform the informal missile defense policy of the United States from one that is limited to one that is robust. For the sake of clarity this will likely require the amending of the 1999 National Missile Defense Act.

•  Continue investments to sustain and modernize current, operational missile defense systems including Aegis, Terminal High Altitude Area Defense (THAAD), and Ground-based Midcourse Defense (GMD), among others, to improve reliability. Investments in a space layer should not come at the expense of necessary sustainment of currently operational systems.

•  Given the growing spectrum of missile threats, the United States must fully integrate and use the space domain to defend access to space, assets in space, as well as the U.S. homeland, allies, and deployed forces.

•  Deploy as soon as possible an SBI capability to provide a robust defense of what the United States values most: The U.S. homeland, space assets, deployed forces, and allies. Ideally, this constellation of satellites with an SBI capability would also be equipped with an SSA capability.

•  Continue investments in directed energy technology to one-day aid or replace space-based kinetic interceptors.

U.S. leaders must make the strategic decision to adapt our space posture and missile defense strategy to optimally defend against present and foreseeable missile threats. The failure to leverage modern technologies that would exponentially improve our security in this way is to choose to remain under-defended, and in some instances, undefended. Remaining vulnerable to current missile threats is to knowingly place the security of Americans and the United States’ military pre-eminence at the mercy of countries like China, Russia, North Korea, and Iran. This is highly unstable, and because it is technically avoidable, wholly unacceptable. We cannot afford to wait until a crisis is upon us before we are spurred to action. Now is the time to act.

This Hudson Institute study on space and the right to self-defense draws upon the invaluable knowledge and experience of a distinguished Senior Review Group. While the members of the group have found consensus on the study’s contents herein, there may be precise wording or areas of emphasis on which there is some disagreement. This study does not necessarily reflect the positions of their current affiliations or that of the U.S. government.

Read the full report at Hudson Institute.