The Cosmic Precipice: Why Weaponizing Space Hurts Us All

The Head of U.S. Space Command, Gen. Stephen Whiting, recently called for a significant ratcheting up of the notion of space as a warfighting domain. Speaking at the 40th Annual Space Symposium, he stated, “It’s time that we can clearly say that we need space fires and we need weapon systems. We need orbital interceptors. And what do we call these? We call these weapons, and we need them to deter a space conflict and to be successful if we end up in such a fight.”¹ To be sure, it is not the first time that a military actor has called for space weaponization, but it is the latest and most explicit call.

In a period of growing geopolitical tensions, with China and Russia increasingly seen as strategic threats, including in space, it may seem that calling for the weaponization of space is a logical next step in national security planning. However, we argue that such a move would not only be strategically counterproductive but also do serious harm to those of us who rely on space for our daily well-being. This is, in large part, because much modern infrastructure on Earth—from communications and finance to weather prediction and navigation—relies on space-based systems.

Fortunately, while military technologies such as satellite-based surveillance and communications have long operated in orbit, space itself is not yet weaponized in the strict sense. This distinction is crucial. The placement of actual weapons in space would cross a significant line, violating the 1967 Outer Space Treaty, a binding agreement that designates space as exclusively for peaceful use to benefit all of humankind. While the treaty only explicitly prohibits placing weapons of mass destruction in space, there also exists a strong taboo against other forms of weaponization—not unlike the nuclear taboo that has helped prevent the use of nuclear weapons for the last eighty years. These international norms and agreements mean that weapons of any kind would constitute a breach of peaceful use that, in turn, could also seriously undermine the integrity of other binding international treaties. Placing weapons in space would also undermine key new agreements, such as the Artemis Accords, which further specify peaceful and cooperative space exploration and resource utilization, including with private sector participation.

Given these worries, calls to weaponize space are at minimum careless and at worst actively harmful. Instead, we ought to be protecting the peaceful use of space as a global commons, both for ourselves and for future generations.

What Does Space Weaponization Actually Mean?

It is important to distinguish between the militarization of space and the weaponization of it, even if the difference is sometimes a bit fuzzy. Space militarization, as it is often understood, involves the use of space resources by the military—GPS, satellite communications, and satellite surveillance all fall into this category. Weaponization, conversely, is generally taken to involve physically locating weapons in space itself. Some might argue that modern warfare often makes these categories difficult to distinguish—military targeting systems that rely on satellites, for example, may seem to create the perception that space infrastructure is a key part of weapons deployment and use in ways that may make them count as weapons themselves. Similarly, if we consider the hacking, jamming, or spoofing of other military infrastructure to be a form of weaponry, space infrastructure is already heavily utilized for such efforts.

However, there are a number of ways to more precisely understand space weaponization. At the center of most conversations are space-to-space weapons. That is, weapons situated in space that are aimed at space infrastructure. Broadly put, these come in two categories—kinetic and radiation. Kinetic weapons include any weapons that fire missiles, push, or physically interfere with objects in Low Earth Orbit (LEO), including Orbital Anti-Satellite (ASAT) Weapons, which are the focus of much of U.S. SPACECOM’s efforts. Radiation weapons, conversely, include methods like laser or electromagnetic pulse (EMP) attacks designed to shut down or disable other space-based systems. Of these, the most destructive is the nuclear bomb. There have been a number of space-based nuclear bomb tests performed over the last century by both the United States and Russia, all between 1958 and 1962. The largest of these, Starfish Prime, created an EMP that was much larger than expected, shutting down several satellites as well as street lights and telephone services in Hawai’i, almost 1,500 km away from the detonation site.²

It is also worth noting that the dual-use nature of many emerging space technologies can make it difficult to clearly define or conceptualize space weapons from more innocuous technology. Many of the technologies being developed for the removal of space junk, for example, can just as easily be used to capture or even destroy military targets in space. Similarly, communication systems that are critical for the coordination of civilian satellites can be used by the military to jam or feed misinformation into target systems. Even space-based infrastructure itself can be used for military purposes if it has its own guidance and movement systems, allowing them to be rammed into other objects in orbit.

There is, currently, clear militarization of space by almost every nation on earth with significant security interests. However, as of our best information today, there are no official kinetic or radiation weapons in space itself.³ Even though the unclear nature of “weaponry” could make it increasingly hard to determine in the years to come, it is important to avoid prematurely characterizing the space weaponization line as having already been crossed by the current state of affairs—there is an important conceptual difference between objects in space being used by the military and the actual stationing of weapons designed for war in orbit. And space weaponization rhetoric risks creating a self-fulfilling prophecy.

The Harms of Crossing the Line into Space Weaponization

There are a number of reasons why deploying weapons to space is clearly harmful. Here, we want to discuss a few of them, putting into context how calls for a new arms race in space are both counter-productive and actively detrimental to the wellbeing of all of us here on earth.

From Space Contestation to Space Wars

As a starting point, putting weapons in space, even without necessarily a desire to end up at war, comes with serious implications that actually undermine the very national security goals that militaries seek to project. Crossing the line into weaponizing space could trigger a rapidly accelerating arms race in space, or a security dilemma. A security dilemma is when two or more countries find themselves quickly competing to build-up weapons for fear that they will be overpowered by the other. This situation threatens to spiral into war because of the instability and risk of miscalculation that ensues. The unfortunate result is that even if no country actually wants war at the outset, they quickly find themselves taking steps that bring them closer to war as fear of vulnerability takes over. If one country were to weaponize space, others would feel that they had no choice but to do the same, leading to a self-fulfilling prophecy where war becomes inevitable.⁴ Even one step prior to placing weapons in space—using conflictual rhetoric—can play a precipitating role in this security dilemma. If countries believe that a conflictual “space race” is underway because others talk about it in this way, they are more likely to cross the line. And once the taboo is broken, further conflictual rhetoric around the actual use of space weapons feeds into the spiral to war. In effect, as international relations constructivists argue, even using war-like language in talking about space has the power to create a self-fulfilling prophecy.⁵

This runaway effect is only the beginning when it comes to analyzing what crossing the line into space weaponization actually means. Another dimension to consider is what “space as the next battlefield”—as the U.S Space Force puts it—means in practice. There are currently no plans to build space-fighting aircraft or have the equivalent of boots-on-the-ground in space. There are no plans for soldiers to actually fight in space. Therefore, in reality, any first step toward a war in space would likely quickly translate into war on Earth. However, a war on Earth after first-strike destruction of satellites would be more dangerous than a war that starts on Earth. The risk of miscalculation and casualties in such a circumstance grows significantly, especially considering that today’s militaries are heavily reliant on space.

There is also the problem of what using space-to-space weapons would do to LEO itself. We have already begun to see what this might look like with the testing of earth-based anti-satellite technology by China, Russia, India, and the United States over the last few decades, each of which generated significant amounts of space junk—fragments of destroyed targets orbiting at high speeds that have the potential to damage other space-based infrastructure, including the International Space Station (ISS). Indeed, after Russia’s demonstration of its ability to destroy satellites, astronauts at the ISS had to retreat to a single pod out of fears of a collision with some of the fragments generated by the test.

Such fragments have been the subject of significant scrutiny over the last few decades, with rising fears that the increase in space junk could lead to a catastrophic feedback loop where the disintegration of one satellite leads to an increase in debris, which in turn could lead to the destruction of more satellites and the creation of more debris, creating a chain reaction that ends with an impenetrable field of debris orbiting in low Earth orbit. Such a debris field would prohibit the launching and maintaining of any further satellites or rockets, even those aimed at going past LEO, since they would be destroyed as they passed through the debris field. Such a catastrophe, known as “Kessler Syndrome,” is the subject of increasing conversations about both how many objects we should allow into LEO and how to remove those that need to be decommissioned.⁶

Even beyond the Kessler Syndrome, there are other ways to achieve long-term impacts on launches. Nuclear weapons, detonated in space, would not only take down electrical systems on Earth. Following such a blast there would then be a persistent radiation belt that could impact the ability of spacecraft to take off from Earth as well as the functioning of satellites in that belt for months or years.

Deterioration of the Peaceful Space Commons: Material Agency and Human Capability

Of course, it should not be news to anyone that active war in space poses a serious threat to all of us. Notably, however, there are harms to weaponizing space even if those weapons are never used.

Space is home to an ever-increasing set of technologies that have significant impact on our personal and social projects here on earth. We rely on satellites every day to function in modern society, and we are beholden to them to help solve some of the most pressing problems and questions that face humanity.

While many people think of communication when they think of how we use satellites, only a small percentage of satellite data is used for this purpose. Those who do rely on satellite communication, however, are often from remote communities that cannot be reached by more traditional underground or underwater cables. Similarly, satellites in geosynchronous earth orbit (GEO) are used to access the internet from remote locations where more traditional infrastructure is not in operation, making it an important technology for particularly vulnerable communities. We have also seen an increase in space-based internet more broadly, with the rise of companies like Starlink, that have proven important in conflicts such as Ukraine, and that are beginning to offer a wide array of internet access options for the general public. This is set to increase over the next few decades with tens of thousands of satellites proposed for launch aimed at creating global internet networks.

What is more substantial is the role played by GPS, including in shipping systems and aviation, which rely on it to navigate to their final destination, maintaining the global supply network. A lesser known role of the technology, however, is that it forms the backbone of almost all modern banking systems—GPS acts to synchronize bank records on a global scale, allowing you to use ATMs or pay for things with a credit or debit card.

Space is also the site of significant scientific infrastructure, both outward and inward looking. Space-based satellites monitor melting ice caps, forest loss, and weather patterns; hunt for methane leaks; and locate resources such as rare-earth minerals. They are also a critical part of modern physics; there are currently thirty-five telescopes in orbit around earth, all of which are working to expand our understanding of the universe and the fundamental laws of nature.

Ethicists have long talked about the important role of technology in expanding and supporting human well-being. Amartya Sen⁷ and Martha Nussbaum⁸ have argued that human well-being is connected to the capabilities we possess—that a person is better off if they are able to drive, for example, or vote, and, conversely, worse off if they lack these freedoms. However, the possession of these capabilities goes beyond simply whether I know how to drive or have a body that is physically capable of managing a vehicle. It also relies on the state of the world outside us: Do cars exist? Do I have access to a car? Are women legally allowed to drive in this part of the world? Am I able to repair my car if it breaks down? As Alex Schafran, Matthew Smith, and Stephen Hall put it, “In order to have the capacity to walk down a road, there needs to be a road.”⁹

Several philosophers have picked up and expanded on these external aspects of agency, noting how many of our actions are reliant on the technologies that enable them. Smith calls this “material agency,” where the physical objects around us are fundamentally intertwined with our capabilities, expanding and shifting them as the technology around us changes.¹⁰ It is clear that space technologies act to increase our capabilities. They allow vulnerable communities access to communication infrastructure, allow us to pay for food, housing, and other important things in our lives, help us to monitor and predict natural disasters and climate change, and help increase our understanding of the universe. These material agencies are not just useful—they help save lives and allow us to pursue important personal and social goals.

All of these projects are possible in part because we view space as a peaceful global commons. It is a region of economic, scientific, and public advancement, rather than a site for war. Shifting the public mentality to it, however, via stationing weapons in space, is akin to mounting rocket launchers in the downtown area of a major city. Regardless of whether you launch them, their very presence will change the way that people view and use these areas. Space infrastructure is expensive—costs of over a billion dollars are fairly standard when it comes to building and launching objects into LEO—and willingness to invest in space will go down if there is a visible possibility of open war destroying expensive satellites. This is especially true if we think that the presence of space weapons significantly increases the risk of war—it is rational, in such cases, for space-based companies to be less willing to expand on, or maintain, existing space infrastructure. There are similar calculations for the scientific research community, which will be less likely to risk investing in satellites to monitor climate change or probe fundamental physics if the military attitude toward space becomes normalized.

These impacts are not only on the immediate infrastructure, however. If we think, as we should, that the new space age will entail the rapid growth of space industries and technologies, the presence of weapons will act to alter these projects, changing not just how fast we grow space-based industries, but also the kinds of projects we think are appropriate for places like LEO: We need only think about what kinds of companies build infrastructure in military zones, as compared to financial districts. Treat space as a war zone, and we will end up encouraging industries oriented toward war like weapons contractors and military research. This will be paired with a much higher barrier for any industry not directly related to military security, since the cost-benefit analysis significantly changes if there is the chance your infrastructure could be destroyed at any time. Conversely, where space is a peaceful domain, there is a much lower barrier for investment in space infrastructure, and a broader attitude toward projects that build up human capital and capacities in space.

Conclusion

The United States has significant interests in maintaining open access to space as a peaceful domain with strong norms of responsible behavior. The 2022 U.S.-led moratorium on direct-ascent missile testing is a good example of leadership in space and effective space diplomacy. Thirty-seven countries have followed suit so far and the United Nations General Assembly overwhelmingly adopted the testing moratorium, with 155 countries voting in favor. It is worth noting that even as Russia and China have threatened to weaponize space and are developing some of the technology to do so, they have not yet crossed this line. Given the profound complexities and consequences surrounding space weaponization, this is not surprising.

The United States and other countries with space forces face a choice. They can continue on the current path of strengthening norms of peaceful use, in line with both the Outer Space Treaty and the Artemis Accords, or they can cross the line into weaponizing space and unleash a dangerous arms race with cascading risks of orbital chaos. We have argued that the long-term interests of humanity are best served by policies that preserve space as a domain for scientific and economic advancement rather than military competition. Despite the dramatic rhetoric of “Space Race 2.0,” the practical realities of space weaponization are far more limited and problematic than they may appear on the surface.

Finally, it is worth noting that many of the harms we have discussed here—the damage to the public perception of the global commons, the instigation of a security dilemma leading to an arms race, and the withdrawal of research and industry interests from space, are all reliant not just on the fact that space is not currently weaponized but also on upholding the legal and normative nature of space as a peaceful domain. This means that militaristic rhetoric around space itself is harmful, in that it changes the way we see space. This is not just about not launching weapons into space, it is also about continuing to talk about space as a global commons, not a military one.

—Ann C. Thresher and Mai'a K. Davis Cross

Ann C. Thresher is an assistant professor in Philosophy and Religion, with a secondary appointment in Public Policy. She is the co-author of The Tangle of Science: Reliability Beyond Rigour, Objectivity, and the Scientific Method, and has published on environmental ethics, biotechnology ethics, the philosophy of physics, and the philosophy of the new space age. She leads the Responsible Sitting working group at the Next Generation Event Horizon Telescope Collaboration, is an Affiliate member of the Black Hole Initiative at Harvard University, and is an associate member of the International Astronomical Union’s Commission C5. She has previously worked at the Stanford Doerr School for Sustainability as an environmental ethicist, and holds a PhD in Philosophy from UC San Diego, and two bachelors degrees from Sydney University, one in Physics and one in Philosophy.

Mai'a K. Davis Cross is the Dean’s Professor of Political Science, International Affairs, and Diplomacy and Director of the Center for International Affairs and World Cultures at Northeastern University. She has written extensively on European security, international cooperation, and space policy. She is author or editor of eight books and special journal issues, including most recently International Cooperation Against All Odds: The Ultrasocial World (Oxford University Press, 2024) and Space Diplomacy (Hague Journal of Diplomacy, 2023). She holds a PhD in Politics from Princeton University, and a bachelor's degree in Government from Harvard University. She is also a member of the Council on Foreign Relations and served on its 2024-5 task force on US Space Policy.

NOTES