Hi, my name is John Gartner. I'm a contributor to the New York Times magazine, and I write about science and technology. This week's Sunday Read is a story I wrote for the magazine Space Issue about the Space Force. It's the newest, smallest, and most secretive branch of the US military. It was established just four years ago and its members, they're called guardians, are in charge of observing and protecting everything that belongs to America that's orbiting above the Earth. That includes defending military satellites and all the satellites we sometimes take for granted that are vital to our day-to-day lives. Unlike, say, the Air Force or even the Coast Guard, you won't see photos of its planes and ships in service. And because so much of its work is out of sight, the Space Force has almost become this caricature. There's even a Netflix comedy series about it starring Steve Carell. The operating cost for the Space Force amount to about $26 billion a year. I don't think it's uncommon to hear questions like, Well, why do we need to spend so much to protect our satellites? Or, Are these Threat Star satellites real or imagined? But picture life without GPS, without mapping and directions, or without weather satellites, which our entire agricultural systems depend on.

Our lives are tied very intimately to what's happening in space. I wanted to find out what does this new branch of the military actually do and how do they do it. After approaching the Space Force and explaining the premise of my story, they agreed to give me some access that I think they don't ordinarily offer. In Colorado, I visited the Peterson and Schriever bases, which were formerly used by the Air Force. I also went to a place called Space Systems Command in Los Angeles, not far from L. A. X. Most of the time, there was a great veil of secrecy over what the Guardians were doing. At Peterson, I couldn't bring any electronic devices into the buildings. I could only go old school and use a notebook. There were some people I couldn't quote by name. Sometimes I'd enter a room and it would need to be vacated before I could walk through it and I'd have to pass through quickly. But I did uncover a lot in my reporting about how and why the Space Force operates, which you'll hear about in my story. One of the most striking things to me was this.

I've always thought of space as a place of wonder and delight and endless curiosity. But the Space Force guardians, in their own words, consider space to be a contested, congested, war-fighting domain. This military branch of about 15,000 people has to prepare for a war in space, even as they do everything they can to prevent a war in space. It's this delicate balancing act between security and the arms race we've entered into with Russia and China, and they have to make sure they don't overstep it. Here's my article. What does the US Space Force actually do? Read by Eric Jason Martin.

Chief Master Sergeant Ron Lurch of the US Space Force sat down in his office in Los Angeles one morning in September to deliver a briefing known as a threat assessment. The current threats in space are less sci-fi than you might expect, but there are a surprising number of them. At least 44,500 space objects now circle Earth, including 9,000 active satellites and 19,000 significant pieces of debris. What's most concerning isn't the sworn of satellites, but the types. We know that there are kinetic kill vehicles, Lurch said. For example, a Russian nesting doll satellite in which a big satellite releases a tiny one and the tiny one releases a mechanism that can strike and damage another satellite. There are machines with the ability to cast nets and extend grappling hooks too. China, whose presence in space now far outpaces Russia's, is launching unmanned space planes into orbit, testing potentially unbreakable quantum communication links and adding AI capabilities to satellites. An intelligence report, Lurch said, predicted the advent within the next decade of satellites with radio frequency jams, chemical sprayers, and lasers that blind and disable the competition. All this would be in addition to the cyber warfare tools, electromagnetic instruments, and ASAT, anti-satellite missiles that already exist on the ground.

In Lurch's assessment, space looked less like a grand new ocean for exploration, phrasing meant to induce wonder that has lingered from the Kennedy administration and more like a robotic battlefield where the conflicts raging on Earth would soon extend ever upward. The Space Force, the sixth and newest branch of the US military, was authorized by Congress and signed into law by President Donald Trump in December 2019. Its creation was not a partisan endeavor, though Trump has boasted that the idea for the organization was his alone. The initiative had, in fact, been shaped within the armed forces and Congress over the previous 25 years, based on the premise that as satellite and space technologies evolved, America's military organizations had to change as well. At its incarnation, the Space Force was an assemblage of programs and teams that already existed, mainly as entities within the Air Force. It's one of the common misperceptions that it cost money to create the Space Force, and it really didn't because we already had Space Forces. Todd Harrison, of the Center for Strategic and International Studies, told me. These were just spread throughout the military: the people, the bases, the platforms, the satellites, the ground stations.

What the new directive did accomplish, however, was to group space endeavors under a central chain of command and authorize its leaders to chart a unified future. One of the things that we were lacking without a Space Force was an organization that would argue for its own destiny. Douglas Livero, a former Pentagon official involved in helping start the branch, told me. The concern was that without a dedicated team within the military's bureaucracy that could push for the specific tools they needed, the United States would be at a disadvantage. Some strategists worried that the nation already was. Livero pointed out that two decades ago, a Chinese military analyst named Wang Hu-Cheng, wrote a paper that presaged an aspect of China's aerospace strategy. For countries that can never win a war with the United States by using the method of tanks and planes attacking the US space system may be an irresistible and most tempting choice. The argument identified space as the US military's soft ribs and strategic weakness. From the start, the Space Force had detractors. Air Force officials wondered if it was necessary, while some political observers believed that it signified the start of a dangerous and expensive militarization of another realm.

What seemed harder to argue against was how nearly every aspect of modern warfare and defense, intelligence, surveillance, communications, operations, missile detection has come to rely on links to orbiting satellites. The recent battles in Eastern Europe, in which Russia has tried to disrupt Ukraine's space-borne communication systems are a case in point. And yet, the strategic exploitation of space now extends well beyond military concerns. Satellite phone systems have become widespread. Positioning and timing satellites such as GPS, now overseen by the Space Force, allow for digital mapping, navigation, banking, and agricultural management. A world without orbital weather surveys seems unthinkable. Modern life is reliant on space technologies to an extent that an interruption would create profound economic and social distress. The work of the Space Force is, by its nature, highly sensitive, often classified, and mostly out of sight. This leaves the organization in a battle for visibility and, at times, viability. Some members of the force, guardians, as they're called, told me that even now they find themselves bumping into members of other branches of the military who see their arm patches and ask in earnest, Space Force, is that a real thing? The Steve Carell Netflix comedy series, which members of the actual Space Force sometimes argue is neither good nor funny, doesn't help their cause.

It likewise doesn't capture their seriousness of purpose. For the moment, the Force has taken up a problem not often contemplated outside science fiction. How do you fight a war in space or a war on Earth that expands into space? And even if you're ready to fight, how do you make sure you don't have a space war in the first place. The Space Forces Operations Division is headquartered on the southeastern side of Colorado Springs in a massive three-storey building within the guarded perimeter of Peterson Space Force Base. Until recently, it was Peterson Air Force Base. The office's inner workings are highly secure and secretive. The force, as one security analyst told me, has a larger proportion of its budget, around $26 billion this year, dedicated to classified spending than any other branch of the military. Visitors to headquarters are not allowed to bring electronic devices or walk unescorted inside. The building, nevertheless, hums with activity, with personnel hustling about under a canopy of scale model satellites, large replicas of machines that now orbit Earth hanging in a bright, airy atrium. When I visited in late September, several military and civilian personnel took me through their day to day work.

Right away, they noted that the Space Force is often mistaken for United States Space Command, also headquartered in Colorado, that reports to the US Secretary of Defense. Space Command is a decision making entity that coordinates space related operations for all branches of the armed forces. The Space Force, by contrast, outfits and trains troops for potential space conflicts, scrutinizes space for dangers, and launches satellites for the Department of Defense. The Space Force regularly consults with space command to ask how or whether the potential threats it discovers should be addressed. As large as the Space Force's remit seems to be, to monitor, protect, and ensure access to a territory far larger than Earth's oceans, technology now enables economies of scale. It's a big domain with the smallest force, smaller than the Coast Guard. Christopher Hears, the technical director to the Deputy Commanding General for Operations, explained. All told, the Space Force has about 8,600 military guardians and about 5,000 civilian guardians. But you don't need hundreds of people to operate a satellite after launch. You may need only one. Space Force personnel often do their work in airconditioned windowless buildings outfitted with computer servers and robust intelligence links.

During critical situations, they deploy in place. That is, they report to the same offices, but at a heightened state of readiness. Gardennordians tend to think of the realm they patrol as a structured, multilevel terrain, Earth as being surrounded by three highways or three rings. The nearest level, Low Earth orbit, Leo, is host to constellations like SpaceX's Starlink network and the International Space Station, which moves about 250 miles above us at 17,500 miles per hour. A medium Earth orbit, Neo, between 1200 and 22,000 miles above is where GPS satellites circle. At the highest ring, at least for now, is a track known as geosynchronous orbit, GEO, because an object in such an orbit keeps pace with Earth's rotation. This band is home to direct TV satellites, weather tracking instruments from the National Oceanic and Atmospheric Administration and Crucial Defense Department communication links. It's a technological zoo up there. The satellite mix is foreign and domestic, young and old, sinister and peaceful. The technologies are all different sizes, flying at different speeds and altitudes. The challenge for the force is to monitor all movement, but also to track the threatening presence of debris, some of which is naturally occurring, tiny rocks, for instance, and some of which has human origins like shards of old rockets.

Because space junk can move at extraordinary velocities, a floating screw might pack a destructive punch equivalent to a small bomb. The main focus within the Space Force is on observation and deterrence. Nobody wants a space war, I was reminded frequently, but the Force has a capacity to mobilize when necessary. At Peterson, I visited an electromagnetic warfare center, a building not far from headquarters, but ringed with surveillance cameras and an additional perimeter of high fencing, where men and women train to unjamp signals that may be intentionally interfering with American planes, ships, and ground troops. It would be like watching TV and you can't get the signal, Lieutenant Colonel D. J. Thomas, who leads the team, told me. In emergencies, Thomas said his guardians would pack up a pair of portable dish antennas and a customized computer console at a moment's notice, a combined unit that struck me as fitting easily into a minivan and ship out to remote locations all over the world. The rooms I visited at the Electromagnetic Warfare Center were for defensive training. A part of the building was given over to offensive tactics. Clearly, the force sees both as necessary. And if a requirement to blind and deafen an enemy's satellites were to arise from US Space Command, the Space Force could help fulfill the order.

The means would most likely not be kinetic, some form of physical or explosive contact, but electronic, a weapon of code-related stealth, or perhaps a debilitating, high-energy burst. Colonel Chandler Atwood of Space Force Operations Command told me that what concerns him most is his belief that Americans are unaware of how rapidly orbital dangers have evolved. He acknowledged that the force observes multiple events daily in space that require its attention. It's not the kinetic threat that keeps me up at night, he added. It's the cyber defense aspect. We have significant vulnerabilities we have to heighten up. From Peterson, I took a 30-minute ride to a smaller Space Force base in Colorado known as Shriever, which sits on a grassy plain with a distant view of Pikes Peak. To reach the Space Force's orbital warfare unit meant passing through a gated station at the base's perimeter and barriers of high protective fencing monitored by guards with body armor and weapons. Lieutenant Colonel Galen Thorp escorted me inside the complex. The most crucial part of his work occurs inside a building where about 120 guardians working in teams of five at a time, push-buttons, as Thorp put it, to drive five maneuverable observation satellites known as G-SAPs for the Geosynchronous Space Situational Awareness Program at a distance of 22,300 miles above Earth.

Unlike many satellites, which cannot be significantly steered once they're put into orbit, these have tanks of propellant and are akin to enormous remote controlled drones. The program was originally created inside the Air Force. I asked Thorp how things had evolved since his unit was reconfigured within the Space Force three years ago. He pointed to a shift in posture from merely cataloging all the satellites in orbit to scrutinizing their behavior using tools like GSAPs in terms of threat awareness, or as he put it, we have to know where these objects are in a protect and defend sense. Thorp's colleague, Captain Raymond Perera, drawing on a whiteboard, pointed me to another concern, the crowd of satellites in low-earth orbit. I would say we're probably already entering into an area where congestion is a problem, he said, and anything that would generate debris would be catastrophic for the domain. One plausible theory is known as the Kessler syndrome, named after the former NASA scientist Donald Kessler, which posits that a release of wreckage and fragments in this orbit could eventually lead to a domino effect of unstoppable destruction. Perera, pointed out that if someone or something were to touch off such an event, they would not only be harming their adversary, they would be harming themselves.

But even short of that, a single collision or attack might hamstring science missions to the moon or to Mars or lead to failures for GPS and communications systems, a problem that could have huge consequences for life on Earth. Keeping track of 44,500 items moving around the planet, along with new arrivals that slip into orbit nearly every week, poses a multidimensional task. Who launched these machines? Why? What could they do? We need to know what's up there, where is it going, and why we should be concerned, Colonel Bryan McLean of the Space Force told me. This goal, known as space domain awareness, has become one of the force's overarching priorities. There are enormous challenges in creating a system of constant observation and making sense of so much data. What constitutes threatening activities in orbit, moreover, and what might necessitate a strategic response is not always clear. In truth, space has few unquestioned laws apart from those relating to gravity. A treaty from the late 1960s signed by most of the major nations on Earth prohibits the use of nuclear weapons in space and designates the moon for peaceful purposes. But recently, I was told, satellites from foreign adversaries have been coming close to machines from the United States and its allies.

The treaty says nothing about such provocations or about grappling hooks, nesting dolls, and cyber warfare. Space Force leaders readily described their guardians as working toward a state of combat readiness, even as they hope an era of actual conflict never arrives. In October, I went to the Pentagon to meet with General Chance Salzman, the Chief of Space Operations, and the Space Force's highest ranking officer. Salzman remarked that several decades back, when he began working with satellites in the Air Force, the notion that there could be combat losses in space was not part of the conversation. But those are discussions now, he told me, because both the Chinese and the Russians have demonstrated operational capabilities that truly placed those assets at risk. In 2007, China's decision to test an ASAT weapon to destroy one of its own satellites sent shockwaves through the US military and created a vast field of debris. A similar Russian tactic in 2021 generated more than 1,500 fragments and led Secretary of State, Anthony Blinkin, to describe the act as recklessly conducted. The Space Force's own squadrons, Saltzman told me, were still tracking pieces of junk that date to the 2007 explosion. You know, the other domains clean themselves up after war.

Saltzman said, You shoot an airplane down, it falls out of the sky. Ships sink out of the sea lanes. Even on land, you bring the bulldozers in and you move things around. But space doesn't heal itself. Debris has led military strategists to ponder a related issue. In space, it's difficult to get out of the way of conflict. Right now, Saltzman noted, if you pull up real time data to see where flights are around the world, the airspace over Ukraine is empty, you will see a void. He said, commercial air traffic does not want to fly over Ukraine. The same thing happens in shipping lanes like the Strait of Hormuz when the Middle East is in turmoil as it is now, so in other domains, refugees, displaced persons, people get out of the way of conflict. Commercial entities move out of the way and avoid conflict. In space, orbital mechanics take over. Machines keep going around and around following the laws of gravity. Nasa satellites may not be able to steer away from a potential combat zone, and commercial entities can't move or won't know where or when to move. And then potentially every satellite becomes more debris, Saltzman remarked.

Every peaceful satellite could become a weapon accidentally. I asked Saltzman what he and his colleagues had learned from observing the war in Ukraine with a caveat that the fighting is hardly over. It could still be a catastrophe on a grand scale, he said. He pointed to several crucial events. The first was how one of Russia's earliest endeavors was to deny Ukrainian troops access to a satellite communications system they relied upon, known as VIASAT, which is stationed in the distant geosynchronous orbital belt. They did it with a cyber attack against the ground infrastructure, he said. You attack the ground network to achieve the space effect you want. This wasn't a surprise to him, he said, yet it was a reminder of the potential power of cyber warfare and how battles to dominate space could still be terrestrial. Another crucial point came after that attack, Ukraine's decision to go to a commercial vendor, SpaceX, and use its Starlink system for combat communications. Here, the lesson was twofold. First, that what Saltzman called commercial augmentation could prove vital in a crisis. As important, he added, Starlink, a configuration of hundreds of proliferated small satellites flying in low-Earth orbit has proved hard to bring down.

The Russians are trying to interrupt it, he said, and they're not having very good success. And the takeaway is that proliferated systems of many small machines in low orbit can be more technologically resilient to hacking and disruption than a few big machines in higher orbits. This seems to fit into Saltzman's goal of maintaining strength during combat while achieving a larger objective of avoiding conflict altogether. If I have two or three satellite communications doing nuclear command and control, maybe those are targets, he explained. But if I take nuclear command and control and spread it across 400 satellites that are zipping over the horizon every 15 minutes, there's a targeting problem. How many satellites do I have to shoot down now to take out the US nuclear command and control? If the answer was 400, it would make things difficult for the enemy. And while small satellites in a large configuration could potentially be a more expensive investment than two or three mega satellites, the shift could be worthwhile. If an adversary believes that it cannot achieve a military objective, Saltzman remarked, it will hesitate to cross a threshold of violence. No conflicts, no debris, no crisis.

Over the course of several days in Los Angeles at Space Systems Command, a Space Force division that plans and acquires technology, I met with about a dozen colonels who detailed their ideas for the next decade. Some discussions addressed the Space Force's goal of being able to launch satellites within, say, 24 hours in urgent situations. I learned the forces working on developing machines that can be refueled in orbit, as well as satellites that can repair other satellites. Because rockets and orbital objects travel so fast, the International Space Station circles Earth every 90 minutes, some tacticians are pondering being able to deliver via launches into space a high-value package, such as a rare medication or a vital part for an F-35 fighter jet halfway across the world in as little as 30 minutes. Other projects are less speculative. There are deep concerns within the military about China and Russia's hypersonic glide weapons, which may be able to avoid defense systems through bursts of speed and pretzeled flight paths. In response, the force is trying to implement a new system of detection in the next several years at low and middle-earth orbits. It took ample funds to build and launch the old systems.

Colonel Heather Bogdee, who helps oversee the program, told me, But with the speed our adversaries are fielding these hypersonic glide vehicles, we don't have the luxury of time anymore. Bryan Wheaton of the Secure World Foundation, a nonprofit that focuses on keeping the orbital realm peaceful and sustainable, told me that the US military has faced perennial challenges in reducing costs and delivery times for new space-based projects and that the Space Force has yet to prove it can buck that trend. Still, the Force is trying to nurture America's domestic rocket industry, acting as a facilitator for national security launches while stoking the growth and bringing down the expense of fledgling commercial enterprises. The Department of Defense sometimes requires big rockets to take heavy satellites farther into space, that is, into the MEO or GEO layers, making for significant technical challenges for new companies. Colonel Douglas Pentecoste, the deputy director of launch enterprise at Space Systems Command, also told me that because some launches carry very precious, super secret instruments, they cannot fail under any circumstances. For now, SpaceX has demonstrated the capabilities and safety record to carry these payloads. But Pentecoste told me, we can't rely on one company to always be there for us.

That's basically taking us back to the 1980s when we were relying on the space shuttle. And then when the space shuttle had its unfortunate accident, we had no way into space for several years. In an effort to diversify risks, Pentecost's team is working with the United Launch Alliance, a partnership of Lockheed, Martin, and Boeing. Commercial companies, Firefly, RocketLab, and Jeff Bezos's Blue Origin, for instance, are in the mix, too. The goal would be a range of reliable and cheaper launch companies to choose from by the late 2020s. Pentecost said he would soon like to be able to get any payload into orbit at any time. There is a darker side that accompanies a future of rampant growth. As space becomes commercialized, it increasingly becomes a geopolitical arena for competition, too. Just as China launched a space plane that stayed aloft for months, so has the US Space Force. Just as competitors develop satellites that make close and unnerving approaches to our satellites, so does the US Space Force. With so many launches now planned and so many designs for enigmatic satellites in the works, it becomes hard not to wonder if the United States will become engaged in a new arms race or to ask if it already has.

In 1950, a political scientist named John Hertz introduced the term security dilemma, noting that in international affairs, a state concerned with being attacked, subjected, dominated, or annihilated by others can be drawn into a vicious circle of building up its defenses. One implication of this, a political scientist named Robert Jarvis later posited is that one state's gain in security inadvertently threatens others. When I asked Saltzman if this was a concern, he acknowledged that it was. But he also said that the security dilemma was a phenomenon that probably dated back thousands of years. Weapons are not inherently offensive or defensive, Saltzman maintained. Weapons are just weapons, and the operations that you choose to undertake with those weapons makes them more offensive or defensive. The important question, as he saw it, was this. At what point does a buildup of defensive weapons in space constitute an ability to conduct offensive operations so that someone else feels threatened? There is a balance here, he said, and this is about stability management. What actions can we take to protect ourselves before we start to cross the line and maybe create a security dilemma? The line, he suggested, harder defined in space, no doubt, and at this point, not clearly defined, had not yet been crossed.