In February 2022, two days into Russia’s invasion of Ukraine, Ukrainian Vice Prime Minister Mykhailo Fedorov tweeted at billionaire Elon Musk, CEO of SpaceX. “While your rockets successfully land from space,” Fedorov wrote, “Russian rockets attack Ukrainian civil people! We ask you to provide Ukraine with Starlink stations.”
Starlink is SpaceX’s constellation of over 3,200 satellites, which the company uses to deliver broadband Internet to more than 1 million subscribers worldwide. Fedorov’s request for Starlink access was urgent: on the morning the invasion began, a Russian cyber attack had caused a “huge loss in communications” in Ukraine. Two days after Fedorov’s tweet, Musk gave his reply: “Starlink service is now active in Ukraine.”
Ukraine has since received some 25,000 Starlink terminals: small, portable satellite dishes that provide Internet connectivity to Ukrainian soldiers and civilians alike. In the words of one Ukrainian soldier: “Starlink is our oxygen.” Through all of this, the US government has played the role of a quiet facilitator, coordinating the purchase and delivery of some 5,000 terminals. In the first two months of the war, the US Agency for International Development reportedly paid SpaceX over $3 million on behalf of Ukraine.
In a world that will soon be orbited by tens of thousands of affordable, interchangeable satellites, anti-satellite weapons promise to be roughly as effective as throwing a rock at a swarm of bees.
Unsurprisingly, Starlink is far less popular in the Kremlin. In late 2020, Russia’s legislative body proposed a law that would fine private citizens up to 30,000 rubles (roughly $400) for accessing Starlink or other non-Russian satellite constellations. It’s not hard to see why — with Russia’s independent media successfully dismantled, the last thing Putin wants is a way for Russian citizens to skirt state censorship.
Since the invasion, Russia has taken aim at Starlink with more than $400 fines. In October 2022, in a direct reference to Starlink, a deputy director of the Russian Foreign Ministry warned that “quasi-civilian infrastructure may become a legitimate target for retaliation.” Such talk, however, is little more than bluster: with the advent of constellations comprising thousands of individual satellites, the offense-defense balance in space is shifting decisively to the latter.
THE OFFENSE-DEFENSE BALANCE IN SPACE
The term “offense-defense balance” refers to the idea that some contexts inherently favor offensive action, while others inherently favor defensive action. These contexts can vary across space: mountains, for example, are widely seen as favoring defense, while open terrain gives the edge to offense. But the offense-defense balance can also vary across time, particularly as technology evolves. It has been argued, for instance, that the invention of the machine gun made the trenches of World War I a defense-dominant environment, while later improvements in motor vehicles and portable radios enabled the offense-dominant blitzkriegs of World War II.
When considering the offense-defense balance in space, it quickly becomes apparent that terrain can be discounted: once in orbit, a satellite launched from the Florida marshes is subject to the same physics as a satellite launched from the Kazakh steppes. Technology, then, must be the primary determinant of whether space as a domain favors offense or defense.
But what distinguishes an offensive space technology from a defensive one? If a Ukrainian drone operator relies on a communications satellite in order to attack a Russian base, is that satellite being used offensively (to attack an enemy position) or defensively (to repel an invading army)? To avoid getting bogged down in philosophy, we can take a cue from space security expert Brad Townsend. According to Townsend, offense in space means harming or interfering with space-borne assets, while defense simply means the absence of offense. Accordingly, we can estimate the offense-defense balance in space by comparing how much it costs the attacker to disable or degrade a space-based capability versus how much it costs the defender to retain that capability.
It is important to note that action in space can be kinetic (like an anti-satellite missile) as well as cyber. Like space, cyberspace has long been seen as an offense-dominant domain, though recent scholarship suggests that this view may be fundamentally flawed. For instance, scholar Rebecca Slayton has calculated that Stuxnet — a computer worm that the United States and Israel used to attack Iranian nuclear facilities — cost the United States and Israel some $300 million to develop and deploy, compared to the mere $14 million that Iran spent on defense, repairs, and lost productivity. And despite decades of concern, the fact that the world has yet to see a “digital Pearl Harbor” indicates that coordinated cyber assaults on high-value targets are likely much harder than many suppose. Therefore, we can focus our attention here on the kinetic dimension of orbital competition.
So why is space seen as favoring offense? The simplest reason is that satellites are vulnerable. Their predictable orbits make them easy to track. Orbital repair and refueling are still in their infancy. Adding defensive measures to a satellite increases its weight at liftoff, meaning your rocket needs extra fuel — and that extra fuel adds weight, creating a need for even more fuel. In short, there is no cost-effective way to defend a satellite. As Townsend observes, “the bullet is always cheaper than the target.”
HOW STARLINK TIPS THE SCALES
So what does Starlink change? On the tactical level, not much. Given the success of anti-satellite tests by China and Russia, a determined state would likely have little trouble shooting down a Starlink satellite. But as Starlink shows, the satellite is no longer the fundamental unit of analysis — the constellation is. And given the sheer size of the Starlink constellation — currently, 3,271 satellites, with a goal of 12,000 by 2026 — some simple math reveals that offense no longer pays.
Consider the cost of a single Starlink satellite. SpaceX deploys Starlink via its Falcon 9 rocket, which carries about 50 satellites per launch. A single Falcon 9 launch sells for $67 million, and each individual satellite is estimated to cost as much as $500,000. Assuming that SpaceX only aims to break even on its Falcon 9 launches, this would mean that each Starlink satellite in orbit costs $1.84 million.
Compare this with the cost of shooting down a Starlink satellite. The last time the United States deployed an anti-satellite missile was in 2008, when it blew up one of its own defective spy satellites. The missile used was an SM-3, which is estimated to cost $9.5 million apiece. This means that if a weapon of this sort were used to shoot down a Starlink satellite, the attacker would be sacrificing a missile that is at least five times more expensive than its target. To make matters worse for the attacker, destroying a single Starlink satellite would have a negligible impact on the defender’s communications, as their ground-based terminal would simply connect seamlessly to another available satellite.
THE VANISHING UTILITY OF KINETIC SPACE POWER
The successes of Starlink have not gone unnoticed. A host of other companies and states are currently at work on their own low-Earth orbit constellations. With Project Kuiper, Amazon is envisioning its own space-based Internet service, and the Chinese startup Galaxy Space has already launched six satellites on the road to its goal of 13,000. Not to be outdone, the European Union is developing a constellation known as IRIS² to support government surveillance, crisis management, and infrastructure protection.
As these Starlink alternatives begin to come online, the defensive advantage in space will only grow. In a world that will soon be orbited by tens of thousands of affordable, interchangeable satellites, anti-satellite weapons promise to be roughly as effective as throwing a rock at a swarm of bees.