Although the U.S. military doctrine was openly considering offensive and defensive space control by 2025, the admission on September 14 by U.S. Air Force Secretary Troy Meink, and confirmed by Space Force chief Gen. Douglas Schiess, that the country has deployed “on-orbit space control weapons” to “defend against hostile adversary action” is cause for concern. Satellite systems increasingly underpin communications, energy, and financial networks and many commercial systems serve civilian and military users. To that end, the U.S., Russia, China, and India, among others, have been developing counter-space capabilities while contributing to the technological and strategic environment rendering earth orbit the next major battlefield. The increasing military use of commercial satellites can endanger the protections they enjoy under international humanitarian law even as this law is underprepared for satellites being highly interconnected and often dual-use. That said, the details that justify the need for orbital defence systems also make poorly specified weapons a potential cause of instability. Mr. Meink described the weapon as defensive, but U.S. military doctrine defines “space control” as encompassing both offensive and defensive operations.

Compounding the consequences of confusion when two steerable satellites approach each other without understanding the other’s intentions — including due to future autonomous satellites running artificial intelligence models onboard — is the lack of policy details. What constitutes “hostile action” and what the weapon can do remain unclear. While the Outer Space Treaty does not ban weapons in orbit per se, Article IV prohibits nuclear weapons or other weapons of mass destruction in orbit — a fluid line considering the centrality of satellite-based networks for contemporary society and the ability of conventional weapons to render damage en masse; its Article III also requires space activities to comply with international law. But when an autonomous, dual-use orbital asset operated by a commercial entity initiates an unwanted defensive strike, the existing rules, including the Liability Convention, cannot be applied straightforwardly to determine accountability. The rules have become too coarse for what contemporary technologies, and the declining esteem for a rules-based world order, warrant. The U.N. Open-Ended Working Group on the ‘Prevention of an Arms Race in Outer Space’ should offer governments an opportunity to address the disclosure. The U.S. government should also reveal the particulars of the weapons it has deployed, and enter into a multilateral governance arrangement that defines exact thresholds of action and escalation.