On April 18, Vice President Kamala Harris announced a U.S. commitment to forgo “destructive direct-ascent anti-satellite missile testing.” This carefully designed ban has the potential to be the first step in a new approach to security and sustainability in space. If so, the United States will be well-positioned to ensure peace and prosperity in space in the emerging era. However, if the U.S. continues its present course, it is unlikely to counter the range of space threats emerging over this decade and beyond.

To succeed, the new U.S. approach must be characterized by three elements. 

First, it must be unilateral and multilateral, synthesizing concerns of both hawks and doves. The U.S. should continue to lead the West in seeking multilateral consensus on norms and agreements, whether voluntary or binding, including with our potential adversaries, particularly China and Russia. At the same time, the U.S. must employ unilateral measures for several purposes: to lead in establishing new rules and norms, to influence other actors’ incentives toward consensus and compliance, and to ensure that deterrence and crisis stability hold even if adversaries refuse to join or subsequently defect from these agreements. Unfettered freedom of action and unilateralism alone are unnecessary and counterproductive, but so is being overly sanguine about the intent of other actors or beholden to slow, consensus-driven international forums — what is needed is a careful synthesis of both unilateral and multilateral measures. Russia’s invasion of Ukraine and China’s anemic response provides a stark reminder that we cannot rely solely on agreements nor presume our values are shared.

Second, it must be nuanced and specific. Sweeping, one-size-fits-all measures are insufficient; instead, the U.S. must carefully assess individual threat vectors on a case-by-case basis and tailor solutions to the unique characteristics of each specific threat. 

Third, it must be timely. Preventing, deterring, and managing these threats will require putting in place appropriate legal frameworks, policies, doctrine, and technological capabilities well in advance — a process that takes years. Therefore, delay is untenable. As Gen. John Hyten, the former Strategic Command and Air Force Space Command chief, noted shortly before his 2021 retirement as vice chairman of the Joint Chiefs of Staff, “the DoD is still unbelievably bureaucratic and slow” in its response to China’s rapidly advancing space weapons. He advised his successor to “reinsert speed into the process.”

Fortunately, Vice President Harris’s ban and recent comments made by other top space officials hint at a possible embrace of all three elements. 

In December, Harris tasked the National Space Council, National Security Council, Department of Defense, Department of State, and other agencies to collaborate on proposals to “advance U.S. interests and preserve the security and sustainability of space.” Harris’s April 18 moratorium on debris-producing, direct-ascent anti-satellite (DA-ASAT) tests was identified by the accompanying White House fact sheet as the “first initiative” of many under this broader effort. The White House statement further clarified the Biden administration’s priorities, declaring that “developing a shared understanding of what constitutes safe and responsible space activities contributes to a more stable space environment by reducing the risk of miscommunication and miscalculation.” It also said the U.S. will “uphold and strengthen a rules-based international order for space,” and that by “working with commercial industry, allies, and partners, [the U.S.] will lead in the development of new measures that contribute to the safety, stability, security, and long-term sustainability of space activities.”

Harris’s announcement drew immediate praise from many and condemnation from a few. Rep. Mike Rogers, ranking member of the House Armed Services Committee (HASC), for example, responded with a statement that “simply declaring [that the U.S. will not conduct destructive DA-ASAT tests] isn’t deterrence,” even suggesting that it might be “the opposite.” Rep. Doug Lamborn, ranking member of the HASC strategic forces subcommittee, went further. By issuing this unilateral moratorium, Lamborn tweeted, the Biden administration “is abandoning its responsibility to maintain United States space superiority” and “creates more opportunities for China and Russia to hold our assets in space at risk while they continue to field ASAT technologies and create hazardous space debris.”

These lawmakers, likely reflecting the sentiment of many hawks, are right to emphasize the importance of deterring Chinese and Russian aggression in space. New ASAT systems are on track to achieve operational status over the next several years, each with distinct threat characteristics and use cases. 

However, Rogers and Lamborn are wrong to suggest that this testing moratorium undercuts deterrence. Instead, it illustrates exactly the nuanced, threat-specific, case-by-case approach — tailoring specific solutions to specific problems — that the U.S. must adopt more widely to counter these emerging 21st-century challenges.

While much media coverage has referred to this as a ban on ASAT testing, that is deliberately not the case. Vice President Harris’s words were carefully chosen: only “destructive direct-ascent anti-satellite missile testing” is prohibited. As John Hill, deputy assistant secretary of defense for space and missile defense, subsequently noted, the ban in no way disadvantages the U.S. because it does not limit “any technological capability” but seeks only to constrain one specific “behavior that we want to dissuade”: namely, debris-generating tests of direct-ascent ASAT missiles. As Hill put it, “this is not just about space security, but … underpinning the long-term ability to continue human exploration … and … economic uses of space.”

This moratorium was specifically designed to address the threat of debris generation from destructive DA-ASAT testing without disadvantaging the United States or any other actor who follows suit. Therefore, it does not impose limits of any kind on development or operational use. It also does not limit any DA-ASAT missile testing deemed non-“destructive,” including flight tests and deliberate near-miss “fly-bys” of orbital targets. Such tests are sufficient to enable DA-ASAT development. Indeed, this has been China’s consistent approach since 2007, and Russia conducted numerous non-destructive tests of the Nudol anti-satellite missile system before conducting a test in November 2021 that destroyed the Soviet-era Cosmos-1408 satellite.

Additionally, as openly acknowledged by Eric Desautels, the acting U.S. deputy assistant secretary for arms control, verification, and compliance, the moratorium “doesn’t cover all ASAT threats, including space-based ASAT systems.” In other words, it does not limit testing of any ASAT or non-ASAT system other than direct-ascent ASAT missiles: active defenses, co-orbital systems, lasers, jammers, and more remain unaffected. Far from undercutting the ban’s efficacy, this nuance is precisely what makes this a potential watershed moment.

The Biden administration has already alluded to the DA-ASAT testing ban as the first of many measures. These measures, taken in combination, will address the space sustainability concerns of the doves and the space security concerns of the hawks. For example, Desautels announced that the U.S. plans to seek consensus regarding a variety of nonbinding international rules of the road, including limits on “purposeful interference” with nuclear command-and-control satellites, limits on testing in the direction of or in close proximity to another country’s satellites, and more. This week, the United States began to lay the groundwork for such measures at the first substantive session of the U.N. Open-Ended Working Group on reducing space threats. Discussions will continue on these measures and others at a second five-day session in 2023, culminating in a report to the U.N. General Assembly in Fall 2023.

These multilateral efforts are laudable but must be coupled with unilateral defenses, and those defenses must be specific and tailored. The U.S. remains hard at work on one-size-fits-all defensive measures, such as operationally responsive space and proliferated constellations of smaller satellites. Still, certain emerging threats cannot be sufficiently countered by generalized defenses alone. The U.S.’s opening National Submission to the U.N. Open-Ended Working Group (OEWG) lays out a clear vision regarding objectives and approach. However, it lacks detail regarding specific threats or specific measures to counter said threats. For example, the document flags on-orbit servicing capabilities as a potential dual-use threat and identifies space-to-space as an important ASAT category. It also flags the principles of “due regard” and “safe separation” — including, in particular, avoidance of “interference with security-related space systems” — as important “starting points” and “areas for further consideration.” However, the U.S. submission does not lay out the unique characteristics and potential impacts of this threat, nor does it address what kinds of specific legal and policy measures might counter it effectively. Similarly, the 2022 assessment of the Defense Intelligence Agency submitted to the OEWG affirms that the space-to-space ASAT threat is growing, but goes no further.

Such vagueness runs the risk of either derailing consensus or producing agreement only on principles so broad and flexible as to be meaningless. Even worse, a lack of specificity would deprive the U.S. Defense Department and other parties of critical guidance on developing doctrine and capabilities. More generally, multilateral approaches can only resolve one piece of the puzzle and must complement rather than drive or substitute for U.S. adoption of appropriate unilateral and security measures.

Vice President Harris’s ASAT test ban was specifically designed to address the hawkish and dovish concerns — to reduce space debris and preserve sustainability while avoiding any elements which would undermine security. The U.S. must adopt similarly nuanced approaches to deal with the security concerns of the hawks. For example, whereas the current U.S. position speaks generically of “safe separation,” “space-to-space ASATs,” and “harmful interference,” the specific threat vectors in this category must instead be named and dealt with one by one. One major concern in this area is the potential pre-positioning of dual-use spacecraft capable of rendezvous and proximity operations (RPOs) near vulnerable, high-value targets in high orbits during crisis or peacetime. Such pre-positioning would be highly destabilizing: a proverbial Sword of Damocles looming over critical systems which have thus far been mostly safe, including GPS in medium Earth orbits and early warning and nuclear command, control, and communications (NC3) in geostationary orbits. In a potential Taiwan conflict later this decade, for example, China might be tempted to leverage such threats to deter U.S. intervention, or even decide to attack these assets in a miscalculated effort to force the U.S. to back down or simply to hamper the U.S.’s strategic and operational capabilities. This threat can be defused almost entirely, but only if dealt with well in advance and only by adopting a properly calibrated two-track approach. 

On the one hand, diplomatic engagement is necessary and appropriate — both coordinating with our allies and engaging with potential adversaries. On the other hand, the U.S. should not be afraid to make unilateral declarations to elucidate our perspective on relevant norms of behavior and the contours of international law. Most importantly, these diplomatic efforts must occur contemporaneously with the U.S. adoption of unilateral measures designed to give teeth to these rules and norms and ensure adequate deterrence and de-escalation tools. Measures might include the fielding and deployment of “bodyguards” to protect these high-value assets; clear articulation of policy contours and a strong legal foundation for “warning/self-defense zones” around such assets; and readying a comprehensive set of graduated-response options. Such actions would ensure that the U.S. can always deter and respond to violations of these internationally agreed-upon rules in a credible and proportionate manner.

Vice President Harris’s ban is a rare example of synthesis between the views of both hawks and doves. It is nuanced, specific, timely, and harnesses both unilateral and multilateral processes. It is also only the first step among many. If the right lessons are learned from it, and if they are then adopted consistently across a range of other threats, the result may be an optimal combination of measures, enabling the U.S. to ensure both peace and prosperity in space and on Earth.


Brian Chow (Ph.D. in physics, MBA with distinction, Ph.D. in finance) is an independent policy analyst with over 160 publications. He can be reached at brianchow.sp@gmail.comBrandon Kelley is the director of debate at Georgetown University, and a graduate student in the Security Studies Program. He can be reached at bwk9@georgetown.edu.

Brian Chow (Ph.D. in physics, MBA with distinction, Ph.D. in finance) is an independent policy analyst with more than 170 publications.